WO2023002341A1

WO2023002341A1 - Hydrofluoroolefins and uses thereof

Info

Publication number: WO2023002341A1
Application number: PCT/IB2022/056588
Authority: WO
Inventors: Sean M. Smith; Markus E. HIRSCHBERG
Original assignee: 3M Innovative Properties Company
Priority date: 2021-07-20
Filing date: 2022-07-18
Publication date: 2023-01-26

Abstract

Hydrofluoroolefin ether compounds are represented by the general formula (I): where Rf 1 is a linear, branched, or cyclic fluoroalkyl group containing 1-5 carbon atoms and may contain up to 2 H atoms, Rf 2 is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N, Rf 3 is an F atom, a CF3 group, or a CF2CF3 group, or Rf 2 and Rf 3 together form a perfluorinated ring structure with 5-6 carbon atoms, and Rf 4 is an F atom, a CF3 group, or a CF2CF3 group.

Description

HYDROFLUOROOLEFINS AND USES THEREOF Summary Disclosed herein are hydrofluoroolefin ether compounds, methods for preparing these compounds and uses for these compounds. In some embodiments, the hydrofluoroolefin ether compound is represented by the general formula (I): where R_f ¹ is a linear, bra containing 1-5 carbon atoms

and may contain up to 2 H atoms, R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N, R_f ³ is an F atom, a CF3 group, or a CF2CF3 group, or Rf² and Rf³ together form a perfluorinated ring structure with 5-6 carbon atoms, and R_f ⁴ is an F atom, a CF₃ group, or a CF₂CF₃ group. Also disclosed are working fluids where the hydrofluoolefin ether compound described above is present in the working fluid at an amount of at least 25% by weight based on the total weight of the working fluid. Methods for preparing hydrofluoroolefin ether compounds are also disclosed. In some embodiments, the method comprises providing a perfluorinated precursor, reacting the perfluorinated precursor with a reaction mixture comprising a fluoride salt in an aprotic organic solvent to form a fluorinated alkoxide salt, quenching the fluorinated alkoxide salt with an electrophile to form a compound of Formula II, and dehydrofluorination of the compound of Formula II with an aqueous solution of a metal hydroxide and a phase transfer catalyst to form a hydrofluoroolefin ether of general Formula I. In some embodiments, the perfluorinated precursor is a perfluorinated acid fluoride with general structure: R_f ²- (CO)-F, where R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N, (CO) is a carbonyl group C=O. In other embodiments, the perfluorinated precursor is a perfluorinated ketone with general structure: R_f ²- (CO)-R_f ³, where R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N, R_f ³ is a CF₃ group, or a CF₂CF₃ group; or R_f ² and R_f ³ together form a perfluorinated ring structure with 5-6 carbon atoms, (CO) is a carbonyl group C=O. In some embodiments, the electrophile has the general structure R_f ¹- CF₂-CH₂-X, where R_f ¹ is a linear, branched, or cyclic fluoroalkyl group containing 1-5 carbon atoms and may contain up to 2 H atoms, and X is a group with the general formula -OSO₂CF₃, -OSO₂CF₂CF₃, or -OSO₂CF₂CF₂CF₂CF₃. Fluorinated compounds of Formula II have the general structure: (R_f ²)(R_f ³)(R_f ⁴)-C-O-CH₂-CF₂-R_f ¹ II where R_f ¹ is a linear, branched, or cyclic fluoroalkyl group containing 1-5 carbon atoms and may contain up to 2 H atoms, R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N, R_f ³ is an F atom, a CF₃ group, or a CF₂CF₃ group; or R_f ² and R_f ³ together form a perfluorinated ring structure with 5-6 carbon atoms, and R_f ⁴ is an F atom, a CF₃ group, or a CF₂CF₃ group. Detailed Description There is an increasing demand for environmentally friendly and low toxicity chemical compounds for use as working fluids that meet demanding performance requirements and can be manufactured cost-effectively. The desired working fluid materials have desirable low ozone-depleting features, low global warming potential (GWP), and are thermally, hydrolytically, and base stable. At the same time the desired working fluid materials must also meet the performance requirements (e.g., nonflammability, solvency, stability, and operating temperature range) of a variety of different applications (e.g., heat transfer, solvent cleaning, deposition coating solvents, and electrolyte solvents and additives). Currently, the materials used in these applications are fluorinated fluids, such as hydrofluoroethers (HFEs), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and hydrochlorofluorocarbons (HCFCs). Generally, the present disclosure provides a new class of fluorinated compounds useful as working fluids. The new fluorinated compounds are oxygen-containing hydrofluoroolefins (HFOs), which provide similar physical properties to existing fluorinated fluids, but generally provide lower atmospheric lifetimes and global warming potentials to provide a more acceptable environmental profile. The hydrofluoroolefins of this disclosure have catenated oxygen atoms, and are described in this disclosure as “hydrofluoroolefin ethers”. These hydrofluoroolefin ethers have the desirable combination of properties of high thermal stability, low toxicity, nonflammability, good solvency, and a wide operating temperature range to meet the requirements of various applications. The compounds also have generally low atmospheric lifetimes, are not ozone-depleting, and have low global warming potentials (GWPs). As used herein, the terms “hydrofluoroolefins” and “HFOs” are used consistent with their commonly understood chemical definitions and refer to unsaturated organic compounds comprising hydrogen, fluorine, and carbon atoms. Unlike traditional hydrofluorocarbons (HFCs) and chlorofluorocarbons (CFCs) which are saturated, HFOs are unsaturated comprising an olefin group. As used herein, “catenated heteroatom” means an atom other than carbon (for example, oxygen, nitrogen, or sulfur) that is bonded to at least two carbon atoms in a carbon chain (linear or branched or within a ring) so as to form a carbon-heteroatom- carbon linkage. As used herein, "fluoro-" (for example, in reference to a group or moiety, such as in the case of "fluoroalkylene" or "fluoroalkyl" or "fluorocarbon") or "fluorinated" means (i) partially fluorinated such that there is at least one carbon-bonded hydrogen atom, or (ii) perfluorinated. As used herein, "perfluoro-" (for example, in reference to a group or moiety, such as in the case of "perfluoroalkylene" or "perfluoroalkyl" or "perfluorocarbon") or "perfluorinated" means completely fluorinated such that, except as may be otherwise indicated, there are no carbon-bonded hydrogen atoms replaceable with fluorine. As used herein, the group “-R_f” is used according to common usage in chemical arts and refers to fluoroalkyl group. The group “-Rf -“ refers to a fluoroalkylene group. As used herein, the term “aqueous” refers to a liquid composition that includes at least water as the majority component, but may also contain minor amounts of additional water-miscible components. In some embodiments, the present disclosure is directed to hydrofluoroolefin ether compounds represented by the following general Formula I: where R_f ¹ is a linear, branched, or

kyl group containing 1-5 carbon atoms and may contain up to 2 H atoms; Rf² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; R_f ³ is an F atom, a CF₃ group, or a CF₂CF₃ group; or R_f ² and R_f ³ together form a perfluorinated ring structure with 5-6 carbon atoms; R_f ⁴ is an F atom, a CF₃ group, or a CF₂CF₃ group. A wide variety of R_f ¹ groups are suitable. In some embodiments, R_f ¹ is a linear fluoroalkyl group containing 1-5 carbon atoms. In other embodiments, R_f ¹ is a linear fluoroalkyl group containing 1-5 carbon atoms and containing 1 H atom. A wide variety of R_f ² , R_f ³, and R_f ⁴ groups and combinations of groups are suitable. In some embodiments, R_f ² is a perfluorinated alkyl group containing 1-3 carbon atoms; and Rf³ and Rf⁴ each is an F atom. In other embodiments, Rf² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; R_f ³ is a CF₃ group, or a CF₂CF₃ group; or R_f ² and R_f ³ together form a perfluorinated ring structure with 5-6 carbon atoms; and R_f ⁴ is an F atom. In yet other embodiments, R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; R_f ³ is a CF₃ group, or a CF₂CF₃ group; and R_f ⁴ is a CF₃ group, or a CF₂CF₃ group. In some embodiments, the fluorine content in the hydrofluoroolefin compounds of the present disclosure may be sufficient to make the compounds non-flammable according to ASTM D-3278-96 e-1 test method (“Flash Point of Liquids by Small Scale Closed Cup Apparatus”). In various embodiments, representative examples of the compounds of general Formula I include the following:

, disclosure may be hydrophobic, relatively chemically unreactive, and thermally stable. The hydrofluoroolefin ether compounds may have a low environmental impact. In this regard, the hydrofluoroolefin ether compounds of the present disclosure may have a global warming potential (GWP) of less than 500, 400, 300, 250, 200, 275, 150, 100, 80, or even 50. As used herein, GWP is a relative measure of the global warming potential of a compound based on the structure of the compound. The GWP of a compound, as defined by the Intergovernmental Panel on Climate Change (IPCC) in 1990 and updated in 2007, is calculated as the warming due to the release of 1 kilogram of a compound relative to the warming due to the release of 1 kilogram of CO₂ over a specified integration time horizon (ITH). In this equati crease of a compound in

the atmosphere (the change in the flux of radiation through the atmosphere due to the IR absorbance of that compound), C is the atmospheric concentration of a compound, ^ is the atmospheric lifetime of a compound, t is time, and i is the compound of interest. The commonly accepted ITH is 100 years representing a compromise between short-term effects (20 years) and longer-term effects (500 years or longer). The concentration of an organic compound, i, in the atmosphere is assumed to follow pseudo first order kinetics (i.e., exponential decay). The concentration of CO2 over that same time interval incorporates a more complex model for the exchange and removal of CO₂ from the atmosphere (the Bern carbon cycle model). Generally, the hydrofluoroolefin ether compositions of the present disclosure have a desirable boiling point range. In some embodiments, the boiling point is no lower than 40, 50, or even 60°C and no higher than 150, 140, 130, 120, 110, 100, 90, or even 80°C. Generally, the hydrofluoroolefin ether compositions of the present disclosure have desirable low temperature properties as demonstrated by determining the pour point. In some embodiments, the desirable low temperature properties are reflected by pour points of less than -40, -50, or even -60°C. Generally, the hydrofluoroolefin ether compositions of the present disclosure have desirable heat transfer properties as demonstrated by determining specific heat values. In some embodiments, the desirable heat transfer properties are reflected by specific heat values of higher than 900, 1,000, 1,050, 1,100, or even 1,150 J/Kg·K (Joules per Kilogram Kelvin). Generally, the hydrofluoroolefin ether compositions of the present disclosure are expected to provide low acute toxicity based on 4-hour acute inhalation studies in rats following U.S. EPA “Health Effects Test Guidelines OPPTS 870.1100 Acute Oral Toxicity” and/or OECD Test No. 436 “Acute Inhalation Toxicity- Acute Toxic Class Method”. In some embodiments, a compound of the present disclosure has a single dose oral median lethal concentration (LC 50) in male and female Sprague-Dawley rats of greater than 1,000, 1,250, 5,000, 10,000, 12,500, 15,000, 18,000, or even 20,000 ppm. The hydrofluoroolefin ether compounds of this disclosure can be prepared following the general reaction schemes shown below in Scheme 1. General Reaction Scheme 1 Scheme 1A [M]F [M]OH R_f ²-(CO)-F ^ [R_f ²CF₂-O] [M] + R_f ¹-CF₂CH₂-X ^ R_f ²CF₂-O-CH₂CF₂Rf¹ ^ R_f ²CF₂-O-CH=CFR_f ¹ f

Scheme 1B [M]F [M]OH R_f ²-(CO)-R_f ³ ^ [R_f ²R_f ³CF-O][M] + R_f ¹-CF₂CH₂-X ^ R_f ²R_f ³CF-O-CH₂CF₂Rf¹ ^ R_f ²R_f ³CF-O-CH=CFR_f ¹

etone a ox e sa t ormu a ormu a Scheme 1C [M]F + silane or TFE [M]OH R_f ²-(CO)-R_f ³ ^ [R_f ²R_f ³R_f ⁴C-O][M] + R_f ¹-CF₂CH₂-X ^ R_f ²R_f ³R_f ⁴C-O-CH₂CF₂Rf¹ ^ R_f ²R_f ³R_f ⁴C-O- CH=CFR_f ¹

Perfluorinated fluorinated compound of compound of Ketone alkoxide salt Formula II Formula I In general, the method comprises providing a perfluorinated precursor compound comprising a perfluorinated acid fluoride or a perfluorinated ketone, reacting the perfluorinated precursor with a reaction mixture comprising a fluoride salt in an aprotic organic solvent to form a fluorinated alkoxide salt, quenching the fluorinated alkoxide salt with an electrophile to form a fluorinated compound of general Formula II, and dehydrofluorination with an aqueous solution of a metal hydroxide and a phase transfer catalyst to form a hydrofluoroolefin ether of general Formula I as described above. In Scheme 1A the perfluorinated precursor is a perfluorinated acid fluoride. Generally, the perfluorinated acid fluoride has the general structure: R_f ²- (CO)-F where R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; and (CO) is a carbonyl group C=O. In Schemes 1B and 1C, the perfluorinated precursor is a perfluorinated ketone. Typically the perfluorinated ketone has the general structure: R_f ²-(CO)-R_f ³ where R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; in these embodiments, Rf³ is a CF3 group, or a CF₂CF₃ group; or R_f ² and R_f ³ together form a perfluorinated ring structure with 5-6 carbon atoms; (CO) is a carbonyl group C=O. Generally, the fluoride salt (represented as [M]F) comprises a metal fluoride salt or a tetraalkylammonium fluoride salt. Suitable fluoride salts include KF (potassium fluoride), RbF (rubidium fluoride), CsF (cesium fluoride), and TBAF (tetrabutylammonium fluoride). The salts are dissolved in one or more aprotic organic solvents. Suitable aprotic organic solvents include glymes (e.g. diglyme, tetraglyme, and DPM (di(propylene glycol) methyl ether)), N,N-dimethylformamide (DMF), N- methylpyrrolidinone (NMP), and N,N-dimethylacetamide (DMA). In Scheme 1C, the fluoride salt and aprotic organic solvent mixture also comprises tetrafluoroethylene (TFE) or perfluoroalkyl trimethyl silane (e.g. TMS-CF₃ or TMS-CF₂CF₃). In this way, Scheme 1C provides a method for preparing compounds of general Formula I where R_f ³ and R_f ⁴ are not F atoms. The combination of the perfluorinated precursor and the fluoride salt (and optionally TFE or perfluoroalkyl trimethyl silane) forms a fluorinated alkoxide salt. This fluorinated alkoxide salt is quenched with an electrophile. Typically, the electrophile has the general structure: R_f ¹-CF₂CH₂-X, where R_f ¹ is a linear, branched, or cyclic fluoroalkyl group containing 1-5 carbon atoms and may contain up to 2 H atoms; and X is -OSO₂CF₃, OSO₂CF₂CF₃, or OSO₂CF₂CF₂CF₂CF₃). The reaction of the fluorinated alkoxide salt and electrophile forms a fluorinated compound of general Formula II: (R_f ²)( R_f ³)( R_f ⁴)-C-O-CH₂-CF₂ R_f ¹ II where R_f ¹ is a linear, branched, or cyclic fluoroalkyl group containing 1-5 carbon atoms and may contain up to 2 H atoms; Rf² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; R_f ³ is an F atom, a CF₃ group, or a CF₂CF₃ group; or R_f ² and R_f ³ together form a perfluorinated ring structure with 5-6 carbon atoms; and R_f ⁴ is an F atom, a CF₃ group, or a CF₂CF₃ group. In some embodiments, the fluorinated compound of general Formula II include:

The fluorinated compound of general Formula II undergoes dehydrofluorination with an aqueous solution of a metal hydroxide and a phase transfer catalyst to form a hydrofluoroolefin ether of general Formula I as described above. Examples of suitable metal hydroxides (represented as [M]OH) include KOH (potassium hydroxide), LiOH (lithium hydroxide), and NaOH (sodium hydroxide). Typically, the phase transfer catalyst is a tetraalkylammonium halide phase transfer catalyst such as TBACl, TBAB, ALIQUAT 336, or benzyltriethylammonium chloride. Also disclosed herein are working fluids. The working fluid comprises the hydrofluoroolefin ether compound of general formula I described above. The hydrofluoroolefin ether compound is present in the working fluid at an amount of at least 25% by weight based on the total weight of the working fluid. In some embodiments, the above-described hydrofluoroolefin ether compounds is a major component of the working fluid. For example, the working fluids may include at least 50%, at least 70%, at least 80%, at least 90%, at least 95%, or at least 99% by weight of the above-described hydrofluoroolefin ether compounds based on the total weight of the working fluid. In addition to the hydrofluoroolefin ether compounds, the working fluids may include a total of up to 75%, up to 50%, up to 30%, up to 20%, up to 10%, or up to 5% by weight of one or more of the following components: alcohols, ethers, alkanes, alkenes, haloalkenes, perfluorocarbons, perfluorinated tertiary amines, perfluoroethers, cycloalkanes, esters, ketones, oxiranes, aromatics, siloxanes, hydrochlorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons, hydrofluoroolefins, hydrochloroolefins, hydrochlorofluoroolefins, hydrofluoroethers, or mixtures thereof, based on the total weight of the working fluid. Such additional components can be chosen to modify or enhance the properties of a composition for a particular use. The working fluids are suitable for a wide variety of uses. In some embodiments, the working fluid comprises a heat transfer fluid, a coating solvent, a foam blowing agent, an electrolyte solvent, an additive for lithium-ion batteries, or a cleaning fluid. In some embodiments, the present disclosure is further directed to an apparatus for heat transfer that includes a device and a mechanism for transferring heat to or from the device. The mechanism for transferring heat may include a heat transfer working fluid that includes a hydrofluoroolefin compounds of the present disclosure. Such devices are described for example in US Patent No.10,717,694. In some embodiments, the hydrofluoroolefin ether compounds of this disclosure can be used in a fire extinguishing compositions. The composition may include one or more co-extinguishing agents. In illustrative embodiments, the co-extinguishing agent may include hydrofluorocarbons, hydrochlorofluorocarbons, perfluorocarbons, perfluoropolyethers, hydrofluoroethers, hydrofluoropolyethers, chlorofluorocarbons, bromofluorocarbons, bromochlorofluorocarbons, hydrobromocarbons, iodofluorocarbons, fluorinated ketones, hydrofluorocarbons, hydrochlorofluorocarbons, perfluorocarbons, perfluoropolyethers, hydrofluoroethers, hydrofluoropolyethers, chlorofluorocarbons, bromofluorocarbons, bromochlorofluorocarbons, iodofluorocarbons, hydrobromofluorocarbons, fluorinated ketones, hydrobromocarbons, fluorinated olefins, hydrofluoroolefins, fluorinated sulfones, fluorinated vinylethers, unsaturated fluoro-ethers, bromofluoroolefins, chlorofluorolefins, iodofluoroolefins , fluorinated vinyl amines, fluorinated aminopropenes and mixtures thereof. In some embodiments, the working fluids of the present disclosure can be used in an apparatus for converting thermal energy into mechanical energy in a Rankine cycle. The apparatus may further include a heat source to vaporize the working fluid and form a vaporized working fluid, a turbine through which the vaporized working fluid is passed thereby converting thermal energy into mechanical energy, a condenser to cool the vaporized working fluid after it is passed through the turbine, and a pump to recirculate the working fluid. The desired thermodynamic characteristics of organic Rankine cycle working fluids are well known to those of ordinary skill and are discussed, for example, in U.S. Pat. Appl. Publ. No.2010/0139274 (Zyhowski et al.). In some embodiments, the present disclosure relates to the use of the hydrofluoroolefin ether compounds of the present disclosure as nucleating agents in the production of polymeric foams and in particular in the production of polyurethane foams and phenolic foams. In this regard, in some embodiments, the present disclosure is directed to a foamable composition that includes one or more blowing agents, one or more foamable polymers or precursor compositions thereof, and one or more nucleating agents that include a hydrofluoroolefin ether compound of the present disclosure. In some embodiments, the hydrofluoroolefin ether compounds of the present disclosure can be used as dielectric fluids in electrical devices (e.g., capacitors, switchgear, transformers, or electric cables or buses) that include such dielectric fluids. For purposes of the present application, the term “dielectric fluid” is inclusive of both liquid dielectrics and gaseous dielectrics. The physical state of the fluid, gaseous or liquid, is determined at the operating conditions of temperature and pressure of the electrical device in which it is used. In some embodiments, the dielectric fluids include one or more hydrofluoroolefin ether compounds of the present disclosure and, optionally, one or more second dielectric fluids. Suitable second dielectric fluids include, for example, air, nitrogen, helium, argon, and carbon dioxide, or combinations thereof. The second dielectric fluid may be a non- condensable gas or an inert gas. Generally, the second dielectric fluid may be used in amounts such that vapor pressure is at least 70 kPa at 25^oC, or at the operating temperature of the electrical device. In some embodiments, the hydrofluoroolefin ether compounds of the present disclosure can be used in coating compositions that include a solvent composition and one or more coating materials which are soluble or dispersible in the solvent composition. In various embodiments, the coating materials of the coating compositions may include pigments, lubricants, stabilizers, adhesives, anti-oxidants, dyes, polymers, pharmaceuticals, release agents, inorganic oxides, and the like, and combinations thereof. For example, coating materials may include perfluoropolyether, hydrocarbon, and silicone lubricants; amorphous copolymers of tetrafluoroethylene; polytetrafluoroethylene; or combinations thereof. Further examples of suitable coating materials include titanium dioxide, iron oxides, magnesium oxide, perfluoropolyethers, polysiloxanes, stearic acid, acrylic adhesives, polytetrafluoroethylene, amorphous copolymers of tetrafluoroethylene, or combinations thereof. In some embodiments, the hydrofluoroolefin ether compounds of the present disclosure can be used in cleaning compositions that include one or more co-solvents. In some embodiments, the hydrofluoroolefin ether compounds may be present in an amount greater than 50 weight percent, greater than 60 weight percent, greater than 70 weight percent, or greater than 80 weight percent based upon the total weight of the hydrofluoroolefin ether compounds and the co-solvent(s). In illustrative embodiments, the co-solvent may include alcohols, ethers, alkanes, alkenes, haloalkenes, perfluorocarbons, perfluorinated tertiary amines, perfluoroethers, cycloalkanes, esters, ketones, oxiranes, aromatics, haloaromatics, siloxanes, hydrochlorocarbons, hydrochlorofluorocarbons, hydrofluorocarbons, hydrofluoroolefins, hydrochloroolefins, hydrochlorofluoroolefins, hydrofluoroethers, or mixtures thereof. The cleaning compositions can be used in either the gaseous or the liquid state (or both), and any of known or future techniques for “contacting” a substrate can be utilized. For example, a liquid cleaning composition can be sprayed or brushed onto the substrate, a gaseous cleaning composition can be blown across the substrate, or the substrate can be immersed in either a gaseous or a liquid composition. Elevated temperatures, ultrasonic energy, and/or agitation can be used to facilitate the cleaning. Various different solvent cleaning techniques are described by B. N. Ellis in Cleaning and Contamination of Electronics Components and Assemblies, Electrochemical Publications Limited, Ayr, Scotland, pages 182-94 (1986). In some embodiments, the present disclosure further relates to electrolyte compositions that include one or more hydrofluoroolefin ether compounds of the present disclosure. The electrolyte compositions may comprise (a) a solvent composition including one or more of the hydrofluoroolefin ether compounds; and (b) at least one electrolyte salt. The electrolyte compositions of the present disclosure exhibit excellent oxidative stability, and when used in high voltage electrochemical cells (such as rechargeable lithium ion batteries) provide outstanding cycle life and calendar life. For example, when such electrolyte compositions are used in an electrochemical cell with a graphitized carbon electrode, the electrolytes provide stable cycling to a maximum charge voltage of at least 4.5V and up to 6.0V vs. Li/Li⁺. Examples These examples are merely for illustrative purposes only and are not meant to be limiting on the scope of the appended claims. All parts, percentages, ratios, etc. in the examples and the rest of the specification are by weight, unless noted otherwise. The following abbreviations are used: mm = millimeters; g = grams; mL = milliliters; L = liters; mmol = millimoles; min = minutes; h = hours; kHz = kilohertz; NMR = Nuclear Magnetic Resonance; GC-FID = Gas Chromatography-Flame Ionization Detection; FTIR = Fourier Transform Infrared. Materials Used in the Examples Material Description St. . ly c., ly

available from, for example, Chemical Point Ltd., Surrey, United Kingdom. m ma fa le te, te, te, te, le ma ma le m od

Potassium hydroxide (85% purity), available from Sigma KOH Aldrich Corp.

Step 1: To a 600 mL stainless steel pressure reactor were added KF (11.0 g, 190 mmol), 2,2,3,3,4,4,4-heptafluorobutylnonafluorobutane sulfonate (83.1 g, 172 mmol), and DMF (50 mL). The reaction vessel was sealed and was then evacuated, backfilled with N₂, and then evacuated again. To the stirring reaction mixture, hexafluoroacetone (30.2 g, 182 mmol) was slowly added at a rate which did not allow for the internal temperature to rise above 30⁰C. The reaction temperature was then slowly raised to 55⁰C followed by an overnight stir. The reaction mixture was then cooled to room temperature followed by the addition of water (100 mL). The resultant mixture was transferred to a separatory funnel. Removal of the aqueous layer yielded 65.7 g of a crude fluorochemical mixture for which GC-FID analysis indicated formation of 1,1,1,2,3,3,3-heptafluoro-2-(2,2,3,3,4,4,4- heptafluorobutoxy)propane (81% uncorrected GC yield). Fractional distillation of the crude fluorochemical fluid produced 1,1,1,2,3,3,3-heptafluoro-2-(2,2,3,3,4,4,4- heptafluorobutoxy)propane (90⁰C, 740 mm/Hg) as a colorless liquid (41.5 g, 62% isolated yield). The purified material was used in the next step. GC-MS analysis confirmed the identity of the isolated material to be 1,1,1,2,3,3,3-heptafluoro-2-(2,2,3,3,4,4,4- heptafluorobutoxy)propane.Step 2: To a 3-neck round bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe were charged KOH (21.5 g, 326 mmol), TBACl (6.0 g, 21.7 mmol), and H₂O (25 mL). With stirring, KOH and TBACl were dissolved completely before the addition of 1,1,1,2,3,3,3-heptafluoro-2- (2,2,3,3,4,4,4-heptafluorobutoxy)propane (40.0 g, 109 mmol). The reaction mixture was stirred vigorously overnight at elevated temperature (80⁰C) and was then allowed to cool back to room temperature and diluted with H₂O (50 mL). Removal of the aqueous layer yielded 27.9 g of a fluorochemical mixture for which GC-FID analysis indicated formation of 2,3,3,4,4,4-hexfluoro-1-(perfluoro-iso-propoxy)but-1-ene (72% uncorrected GC yield). Fractional distillation of the crude fluorochemical fluid produced 2,3,3,4,4,4-hexfluoro-1- (perfluoro-iso-propoxy)but-1-ene (79⁰C, 740 mm/Hg) as a colorless liquid (24.9 g, 66% isolated yield), Example 1. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR. Example 2: Preparation of 2,3,3,3-tetrafluoro-1-(perfluoro-iso-propoxy)prop-1-ene. Step 1: To a 300 mL stainless steel pressure reactor were added KF (14.5 g, 250 mmol), 2,2,3,3,3-pentafluoropropyltrifluoromethane sul

ate (67.1 g, 238 mmol), and DMF (75 mL). The reaction vessel was sealed and was then evacuated, backfilled with N₂, and then evacuated again. To the stirring reaction mixture, hexafluoroacetone (41.5 g, 250 mmol) was slowly added at a rate which did not allow for the internal temperature to rise above 30⁰C. The reaction temperature was then slowly raised to 50⁰C followed by an overnight stir. The reaction mixture was then cooled to room temperature followed by the addition of water (100 mL). The resultant mixture was transferred to a separatory funnel. Removal of the aqueous layer yielded 65.2 g of a crude fluorochemical mixture for which GC-FID analysis indicated formation of 1,1,1,2,3,3,3-heptafluoro-2-(2,2,3,3,3- pentafluoropropoxy)propane (72% uncorrected GC yield). Fractional distillation of the crude fluorochemical fluid produced 1,1,1,2,3,3,3-heptafluoro-2-(2,2,3,3,3- pentafluoropropoxy)propane (65⁰C, 740 mm/Hg) as a colorless liquid (46.2 g, 61% isolated yield). The purified material was used in the next step. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR. Step 2: To a 3-neck round bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe were charged KOH (3.1 g, 47 mmol), TBPBr (1.6 g, 4.7 mmol), and H₂O (7 mL). With stirring, KOH and TBPBr were dissolved completely before the addition of 1,1,1,2,3,3,3-heptafluoro-2-(2,2,3,3,3-pentafluoropropoxy)propane (5.0 g, 16 mmol). The reaction mixture was stirred vigorously overnight at elevated temperature (80⁰C) and was then allowed to cool back to room temperature and diluted with H₂O (20 mL). Removal of the aqueous layer yielded a fluorochemical mixture for which GC-FID analysis indicated complete conversion of the starting material. Filtration (0.45 micrometer PVDF syringe filter) produced 2,3,3,3-tetrafluoro-1-(perfluoro-iso- propoxy)prop-1-ene as a colorless liquid (2.8 g, 60% isolated yield), Example 2. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR.

Example 3: Preparation of 2,3,3,4,4,4-hexafluoro-1-(perfluoropropoxy)but-1-ene. Step 1: To a 300 mL stainless steel pressure reactor were added CsF (28.8 g, 190 mmol), tetraglyme (75 mL), and 2,2,3,3,4,4,4-heptafluorobutylnonafluorobutane sulfonate (87.1 g, 181 mmol). The reaction vessel was sealed and was then evacuated, backfilled with N₂, and then evacuated again. To the stirring, heated (30⁰C) reaction mixture, perfluoropropionyl fluoride (30.2 g, 182 mmol) was slowly added over the course of 30 min. The resultant reaction mixture was then slowly raised to 70⁰C followed by an overnight stir. The reaction temperature was then cooled to room temperature followed by the addition of water (100 mL). The resultant mixture was transferred to a separatory funnel. Removal of the aqueous layer yielded 87.1 g of a crude fluorochemical mixture for which GC-FID analysis indicated formation of 1,1,1,2,2,3,3-heptafluoro-3-(1,1,2,2,3,3,3- heptafluoropropoxy)butane (74% uncorrected GC yield). Fractional distillation of the crude fluorochemical fluid produced 1,1,1,2,2,3,3-heptafluoro-3-(1,1,2,2,3,3,3- heptafluoropropoxy)butane (92⁰C, 740 mm/Hg) as a colorless liquid (40.6 g, 61% isolated yield). The purified material was used in the next step. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR. Step 2: To a 3-neck round bottom flask equipped with a magnetic stir bar and reflux condenser were charged KOH (16.1 g, 245 mmol), TBACl (9.1 g, 33 mmol), and water (30 mL). With stirring, KOH and TBACl were dissolved completely before the addition of 1,1,1,2,2,3,3-heptafluoro-3-(1,1,2,2,3,3,3-heptafluoropropoxy)butane (30 g, 82 mmol). The reaction mixture was stirred vigorously overnight at elevated temperature (80⁰C) and was then allowed to cool back to room temperature and diluted with H₂O (50 mL). Removal of the aqueous layer yielded 21.2 g of a fluorochemical mixture for which GC-FID analysis indicated formation of 2,3,3,4,4,4-hexafluoro-1-(perfluoropropoxy)but- 1-ene (73% uncorrected GC yield). Fractional distillation of the crude fluorochemical mixture produced 2,3,3,4,4,4-hexafluoro-1-(perfluoropropoxy)but-1-ene (83⁰C, 740 mm/Hg) as a colorless liquid (19.5 g, 69% isolated yield), Example 3. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR.

Example 4: Preparation of 1,1,1,2,2,3,3-heptafluoro-3-(2,3,3,3-tetrafluoroprop-1- enoxy)propane. Step 1: To a 3-neck round-bottom flask equipped with a magnetic stir bar and dry ice condenser was charged KF (17.3 g, 298 mmol). The reaction vessel was then evacuated and backfilled with nitrogen three times before adding tetraglyme (150 mL). To the resultant stirring mixture was added CF₃CF₂CH₂ONf (117.1 g,271 mmol) in one portion followed by the slow addition of perfluoropropionyl fluoride (45 g, 271 mmol) over the course of 20 minutes. After an overnight stir at room temperature, the resultant reaction mixture was diluted with water (50 mL). The diluted mixture was then transferred to a separatory funnel and then further diluted with additional water (450 mL). Removal of the aqueous layer yielded 89.9 g of a fluorochemical mixture for which GC-FID analysis indicated formation of 1,1,1,2,2,3,3-heptafluoro-3-(2,2,3,3,3-pentafluoropropoxy)propane (68% uncorrected GC yield). Fractional distillation of the crude fluorochemical mixture produced 1,1,1,2,2,3,3-heptafluoro-3-(2,2,3,3,3-pentafluoropropoxy)propane (69.5⁰C, 740 mm/Hg) as a colorless liquid (45.5 g, 53% isolated yield). The purified material was used in the next step. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR. Step 2: To a 3-neck round bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe were charged KOH (6.2 g, 95 mmol), TBPBr (4.3 g, 13 mmol), and H₂O (10 mL). With stirring, KOH and TBPBr were dissolved completely before the addition of 1,1,1,2,2,3,3-heptafluoro-3-(2,2,3,3,3-pentafluoropropoxy)propane (10.1 g, 31.8 mmol). The reaction mixture was stirred vigorously overnight at elevated temperature (80⁰C) and was then allowed to cool back to room temperature and diluted with H₂O (20 mL). Removal of the aqueous layer yielded a fluorochemical mixture for which GC-FID analysis indicated complete conversion of the starting material. Filtration (0.45 micrometer PVDF syringe filter) produced 1,1,1,2,2,3,3-heptafluoro-3-(2,3,3,3- tetrafluoroprop-1-enoxy)propane (6.9 g, 73% isolated yield) as a colorless liquid, Example 4. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR.

Example 5: Preparation of 2,3,3,4,4,4-hexafluoro-1-(perfluorocyclopentoxy)but-1-ene. Step 1: To a 1 L 3-neck round bottom flask equipped with a dry ice condenser, magnetic stir bar, and temperature probe were added DCM (500 mL), triethylamine (101 g, 1.0 mol). The resultant mixture was cooled with stirring to 5⁰C followed by the slow addition of 2,2,3,3,4,4,4-heptafluorobutanol (200 g, 1.0 mol). PESF (206 g, 1.0 mol) was then slowly added to the cooled reaction mixture over the course of 30 min at rate which avoided temperature increases above 10⁰C. The resultant mixture was allowed to stir for 1 h at the same temperature before allowing to rise to room temperature. The mixture was then transferred to a separatory funnel followed by washing with water (1 x 250 mL and then 2 x 100 mL) followed by washing with 1 M HCl (100 mL). The bottom, organic layer was then dried over anhydrous Na₂SO₄, concentrated under reduced pressure via rotavap, and then analyzed by GC-FID which indicated formation of 2,2,3,3,4,4,4- heptafluorobutylpentafluoroethane sulfonate (349 g at 98% purity, 90% isolated yield). The purified material was used in the next step without further purification. Step 2: To a 600 mL stainless steel pressure reactor were added added KF (11.2 g, 193 mmol), 2,2,3,3,4,4,4-heptafluorobutylpentafluoroethane sulfonate (67.0 g, 175 mmol), and DMF (100 mL). The reaction vessel was sealed and was then evacuated, backfilled with N₂, and then evacuated again. To the stirring reaction mixture, perfluorocyclopentanone (40.1 g, 176 mmol) was slowly added at a rate which did not allow for the internal temperature to rise above 28⁰C. The reaction temperature was then slowly raised to 50⁰C followed by an overnight stir. The reaction mixture was then cooled to room temperature followed by the addition of water (150 mL). The resultant mixture was transferred to a separatory funnel. Removal of the aqueous layer yielded 68.8 g of a crude fluorochemical mixture for which GC-FID analysis indicated formation of 1,1,2,2,3,3,4,4,5-nonafluoro-5-(2,2,3,3,4,4,4-heptafluorobutoxy)cyclopentane (78% uncorrected GC yield). Fractional distillation of the crude fluorochemical fluid produced

, , , , , , , , -nona uoro- -( , , , , , , - epta uoro utoxy)cyc opentane ( , 740 mm/Hg) as a colorless liquid (43.9 g, 58% isolated yield). The purified material was used

n t e next step. Con rmat on o t e c emca compound was obta ned by convent onal proton and fluorine NMR. Step 3: To a 3-neck round bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe were charged KOH (2.4 g, 36 mmol), TBPBr (1.6 g, 4.8 mmol), and H₂O (7 mL). With stirring, KOH and TBPBr were dissolved completely before the addition of 1,1,2,2,3,3,4,4,5-nonafluoro-5-(2,2,3,3,4,4,4- heptafluorobutoxy)cyclopentane (5.0 g, 12 mmol). The reaction mixture was stirred vigorously overnight at elevated temperature (80⁰C) and was then allowed to cool back to room temperature and diluted with H₂O (20 mL). Removal of the aqueous layer yielded a fluorochemical mixture for which GC-FID analysis indicated complete conversion of the starting material. Filtration (0.45 micrometer PVDF syringe filter) produced 2,3,3,4,4,4- hexafluoro-1-(perfluorocyclopentoxy)but-1-ene as a colorless liquid (3.3 g, 69% isolated yield), Example 5. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR.

Example 6: Preparation of 1,1,1,2,2,4,4,4-octafluoro-3-(2,3,3,3-tetrafluoroprop-1-enoxy)- 3-(trifluoromethyl)butane). Step 1: To a 600 mL stainless steel pressure reactor were added tetraglyme (100 mL), KF (16.1 g, 277 mmol), and 18-crown-6 (10.5 g, 39.7 mmol). The vessel was sealed and then evacuated under reduced pressure, back-filled with N₂, and then evacuated again. 2,2,3,3,3-Pentafluoropropionyl fluoride (43.0 g, 259 mmol) was then added to the stirring mixture. TMSCF₃ (77.3 g, 544 mmol) was then slowly added to the reaction mixture over the course of 1 hour with observed temperature increases up to 45⁰C. The resultant reaction mixture was allowed to stir overnight at room temperature and was then transferred to a 250 mL round-bottom flask equipped with a magnetic stir bar, and reflux condenser. With stirring, the TMS-F by-product was removed by sweeping the mixture with a steady stream of N₂. The resultant mixture was used for the next step without further purification. Step 2: A portion of reaction mixture containing approximately 100 mmol of the potassium alkoxide salt from Step 1 was transferred to a round-bottom three-neck flask equipped with a temperature probe and magnetic stir bar. To the heated (60⁰C) mixture, CF₃CF₂CH₂OTf (25.2 g, 89.3 mmol) was added dropwise over the course of 0.5 h. After an overnight stir at the same temperature, the resultant mixture was allowed to cool to room temperature followed by the addition of water (50 mL). The mixture was then transferred to a separatory funnel followed by dilution by additional water (100 mL). Removal of the aqueous layer yielded 46.5 g of a crude fluorochemical mixture for which GC-FID analysis indicated formation of 1,1,1,2,2,4,4,4-octafluoro-3-(2,2,3,3,3- pentafluoropropoxy)-3-(trifluoromethyl)butane (78% uncorrected GC yield). Fractional distillation of the crude fluorochemical mixture produced 1,1,1,2,2,4,4,4-octafluoro-3- (2,2,3,3,3-pentafluoropropoxy)-3-(trifluoromethyl)butane (108.9⁰C, 740 mm/Hg) as a colorless liquid (19.2 g, 51% isolated yield). The isolated material was used in the next step: GC-MS analysis confirmed the identity of the isolated material to be that of 1,1,1,2,2,4,4,4-octafluoro-3-(2,2,3,3,3-pentafluoropropoxy)-3-(trifluoromethyl)butane. Step 3: To a round-bottom flask equipped with a magnetic stir bar were charged KOH (0.95 g, 14 mmol), TBACl (0.40 g, 1.4 mmol), and H₂O (2 mL). With stirring, KOH and TBPBr were dissolved completely before the addition of 1,1,1,2,2,4,4,4-octafluoro-3- (2,2,3,3,3-pentafluoropropoxy)-3-(trifluoromethyl)butane (2.0 g, 4.8 mmol). The reaction mixture was stirred vigorously overnight at elevated temperature (80⁰C) and was then allowed to cool back to room temperature and diluted with H₂O (5 mL). Removal of the aqueous layer yielded a fluorochemical mixture for which GC-FID analysis indicated >90% conversion of the starting material. Filtration (0.45 micrometer PVDF syringe filter) produced 1,1,1,2,2,4,4,4-octafluoro-3-(2,3,3,3-tetrafluoroprop-1-enoxy)-3- (trifluoromethyl)butane) as a colorless liquid (1.32 g at 87% purity, 60% isolated yield), Example 6. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR.

Example 7: Preparation of 1,1,1,2,2,4,4,4-octafluoro-3-(2,3,3,4,4,4-hexafluorobut-1- enoxy)-3-(trifluoromethyl)butane. Step 1: To a 600 mL stainless steel pressure reactor were added tetraglyme (100

F (16.1 g, 277 mmol), and 18-crown-6 (10.5 g, 39.7 mmol). The vessel was sealed and then evacuated under reduced pressure, back-filled with N₂, and then evacuated again. 2,2,3,3,3-Pentafluoropropionyl fluoride (43.0 g, 259 mmol) was then added to the stirring mixture. TMSCF₃ (77.3 g, 544 mmol) was then slowly added to the reaction mixture over the course of 1 hour with observed temperature increases up to 45⁰C. The resultant reaction mixture was allowed to stir overnight at room temperature and was then transferred to a 250 mL round-bottom flask equipped with a magnetic stir bar, and reflux condenser. With stirring, the TMS-F by-product was removed by sweeping the mixture with a steady stream of N₂. The resultant mixture was used for the next step without further purification. Step 2: Half of the mixture from Step 1 was transferred to a round-bottom three- neck flask equipped with a temperature probe and magnetic stir bar. To the heated (60⁰C) mixture, 2,2,3,3,4,4,4-Heptafluorobutylnonafluorobutane sulfonate (62.7 g, 130 mmol) was added dropwise over the course of 0.5 h. After an overnight stir at the same temperature, the resultant mixture was allowed to cool to room temperature followed by the addition of water (50 mL). The mixture was then transferred to a separatory funnel followed by dilution by additional water (100 mL). Removal of the aqueous phase yielded 55.1 g of a crude fluorochemical layer for which GC-FID analysis indicated formation of 1,1,1,2,2,4,4,4-octafluoro-3-(2,2,3,3,4,4,4-heptafluorobutoxy)-3-(trifluoromethyl)butane (73% uncorrected GC yield). Fractional distillation of the crude fluorochemical mixture produced 1,1,1,2,2,4,4,4-octafluoro-3-(2,2,3,3,4,4,4-heptafluorobutoxy)-3- (trifluoromethyl)butane (136⁰C, 740 mm/Hg) as a colorless liquid (31.4 g, 67% isolated yield). The purified material was used in the next step. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR. Step 3: To a 3-neck round bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe were charged KOH (2.1 g, 32 mmol), TBPBr (2.9 g, 8.5 mmol), and H₂O (5 mL). With stirring, KOH and TBPBr were dissolved completely before the addition of 1,1,1,2,2,4,4,4-octafluoro-3-(2,2,3,3,4,4,4-heptafluorobutoxy)-3- (trifluoromethyl)butane (5.0 g, 10.7 mmol). The reaction mixture was stirred vigorously

overn g t at e evate temperature (80 C) an was t en a owe to coo ac to room temperature and diluted with H₂O (20 mL). Removal of the aqueous layer yielded a fluorochemical mixture for which GC-FID analysis indicated approximately 85% conversion of the starting material. Filtration (0.45 micrometer PVDF syringe filter) produced 1,1,1,2,2,4,4,4-octafluoro-3-(2,3,3,4,4,4-hexafluorobut-1-enoxy)-3- (trifluoromethyl)butane as a colorless liquid (3.4 g at 84% purity, 60% isolated yield), Example 7. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR.

xamp e 8: reparation of 1,1,1,3,3,3-hexafluoro-2-(2,3,3,4,4,4-hexafluorobut-1-enoxy)- 2-(trifluoromethyl)propane. Step 1: To a 600 mL stainless steel pressure reactor were added KF (2

. g, 355 mmol) and DMF (105 mL). The reactor was sealed and evacuated, backfilled with nitrogen, and then evacuated again. To the stirring mixture, hexafluoroacetone (50.1 g, 302 mmol) was slowly added over the course of 10 min. After the temperature of the resultant mixture cooled to 25⁰C, TMSCF₃ (47.2 g, 332 mmol) was slowly added over the course of 30 min via an argon-pressurized cylinder. After complete addition, the resultant reaction mixture was allowed to stir overnight at room temperature before being transferred to a 250 mL 3-neck rounds-bottom flask. The mixture was heated to 70⁰C with nitrogen sweeping the headspace to removed TMS-F by-product. The resultant mixture was used in the next step without additional purification. Step 2: A 250 mL 3-neck round-bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe was evacuated and backfilled with nitrogen three times before addition of half of the mixture from Step 1. With stirring, the mixture was slowly heated to 45⁰C followed by the dropwise addition of CF₃CF₂CF₂CH₂ONf (72.5 g, 150 mmol). The temperature of the resultant reaction mixture was raised to 60⁰C followed by an overnight stir. The mixture was then allowed to cool to room temperature before the slow addition of water (150 mL). The diluted mixture was transferred, and removal of the aqueous layer yielded a crude fluorochemical mixture for which purification via fractional distillation produced 1,1,1,3,3,3-hexafluoro-2-(2,2,3,3,4,4,4-heptafluorobutoxy)-2- (trifluoromethyl)propane (108⁰C, 740 mm/Hg) as a colorless liquid (30.4 g, 48% isolated yield). The purified material was used in the next step. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR. Step 3: To a 3-neck round bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe were charged KOH (1.3 g, 20 mmol), TBPBr (0.91 g, 2.7 mmol), and H₂O (5 mL). With stirring, KOH and TBPBr were dissolved completely before the addition of 1,1,1,3,3,3-hexafluoro-2-(2,2,3,3,4,4,4-heptafluorobutoxy)-2- (trifluoromethyl)propane (2.8 g, 6.7 mmol). The reaction mixture was stirred vigorously overnight at elevated temperature (80⁰C) and was then allowed to cool back to room temperature and diluted with H₂O (20 mL). Removal of the aqueous layer yielded a fluorochemical mixture for which GC-FID analysis indicated approximately 75% conversion of the starting material. Filtration (0.45 micrometer PVDF syringe filter) produced 1,1,1,3,3,3-hexafluoro-2-(2,3,3,4,4,4-hexafluorobut-1-enoxy)-2- (trifluoromethyl)propane as a colorless liquid (2.0 g at 83% purity, 62% isolated yield), Example 8. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR.

Example 9: Preparation of 1,1,1,3,3,3-hexafluoro-2-(2,2,3,3,3-pentafluoropropoxy)-2- (trifluoromethyl)propane. Step 1: To a 600 mL stainless steel pressure reactor were added KF (20.6 g, 355 mmol) and DMF (105 mL). The reactor was sealed and evacuated, backfilled with nitrogen, and then evacuated again. To the stirring mixture, hexafluoroacetone (50.1 g, 302 mmol) was slowly added over the course of 10 min. After the temperature of the resultant mixture cooled to 25⁰C, TMSCF₃ (47.2 g, 332 mmol) was slowly added over the course of 30 min via an argon-pressurized cylinder. After complete addition, the resultant reaction mixture was allowed to stir overnight at room temperature before being transferred to a 250 mL 3-neck rounds-bottom flask. The mixture was heated to 70⁰C with nitrogen sweeping the headspace to removed TMS-F by-product. The resultant mixture was used in the next step without additional purification. Step 2: A 250 mL 3-neck round-bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe was evacuated and backfilled with nitrogen three times before addition of half of the mixture from Step 1. With stirring, the mixture was slowly heated to 45⁰C followed by the dropwise addition of CF₃CF₂CH₂ONf (65.1 g, 151 mmol). The temperature of the resultant reaction mixture was raised to 60⁰C followed by an overnight stir. The mixture was then allowed to cool to room temperature before the slow addition of water (150 mL). The diluted mixture was transferred, and removal of the aqueous layer yielded a crude fluorochemical mixture for which purification via fractional distillation produced 1,1,1,3,3,3-hexafluoro-2-(2,2,3,3,3-pentafluoropropoxy)-2- (trifluoromethyl)propane (85⁰C, 740 mm/Hg) as a colorless liquid (29.5 g, 53% isolated yield). The isolated material was used in the next step. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR. Step 3: To a 3-neck round bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe were charged KOH (2.7 g, 40.7 mmol), TBPBr (1.8 g, 5.4 mmol), and H₂O (5 mL). With stirring, KOH and TBPBr were dissolved completely before the addition of 1,1,1,3,3,3-hexafluoro-2-(2,2,3,3,3-pentafluoropropoxy)-2- (trifluoromethyl)propane (5.0 g, 13.6 mmol). The reaction mixture was stirred vigorously overnight at elevated temperature (80⁰C) and was then allowed to cool back to room temperature and diluted with H₂O (20 mL). Removal of the aqueous layer yielded a fluorochemical mixture for which GC-FID analysis indicated approximately 93% conversion of the starting material. Filtration (0.45 micrometer PVDF syringe filter) produced 1,1,1,3,3,3-hexafluoro-2-(2,2,3,3,3-pentafluoropropoxy)-2- (trifluoromethyl)propane as a colorless liquid (3.2 g at 90% purity, 61% isolated yield), Example 9. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR.

Example 10: Preparation of 2,3,3,4,4,5,5-heptafluoro-1-(perfluoropropoxy)but-1-ene. Step 1: To a 3-neck 500 mL round bottom flask equipped with a dry ice condenser, magnetic stir bar, and temperature probe was added KF (23.5 g, 405 mmol). The reaction vessel was then evacuated and backfilled with nitrogen three times before charging with tetraglyme (225 mL). The stirring mixture was cooled to an internal temperature of -10⁰C and was then charged with perfluoropropionyl fluoride (66.0 g, 398 mmol). At the same temperature, 2,2,3,3,4,4,5,5-octafluoropropylnonafluorobutane sulfonate (172 g, 335 mmol) was then slowly added over the course of 30 minutes. After slowly warming to room temperature during an overnight stir, the resultant reaction mixture was diluted with water (100 mL), transferred to a 1 L separatory funnel, and then diluted with an additional portion of water (300 mL). Removal of the aqueous layer yielded 173 g of a crude fluorochemical mixture for which GC-FID analysis indicated formation of 1,1,2,2,3,3,4,4- octafluoro-5-(1,1,2,2,3,3,3-heptafluoropropoxy)pentane (53% uncorrected GC yield). Fractional distillation of the crude fluorochemical fluid produced 1,1,2,2,3,3,4,4- octafluoro-5-(1,1,2,2,3,3,3-heptafluoropropoxy)pentane (125⁰C, 740 mm/Hg) as a colorless liquid (51 g, 38% isolated yield). The purified material was used in the next step. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR. Step 2: To a 3-neck round bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe were charged KOH (19.8 g, 300 mmol), TBPBr (13.6 g, 40.0 mmol), and H₂O (45 mL). With stirring, KOH and TBPBr were dissolved completely before the addition of 1,1,2,2,3,3,4,4-octafluoro-5-(1,1,2,2,3,3,3- heptafluoropropoxy)pentane (40.0 g, 100 mmol). The reaction mixture was stirred vigorously overnight at elevated temperature (80⁰C) and was then allowed to cool back to room temperature and diluted with H2O (100 mL). Removal of the aqueous layer yielded 24.6 g of a crude fluorochemical mixture for which GC-FID analysis indicated complete conversion of the starting material and formation of 2,3,3,4,4,5,5-heptafluoro-1- (perfluoropropoxy)but-1-ene (59% uncorrected GC yield). Purification of the fluorochemical mixture via fractional distillation produced 2,3,3,4,4,5,5-heptafluoro-1- (perfluoropropoxy)but-1-ene (108⁰C, 740 mm/Hg) as a colorless liquid (18.2 g, 48% isolated yield), Example 10. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR.

Example 11: Preparation of 1,1,1,2,2,3,3-heptafluoro-3-(2,3,3-trifluoroprop-1- enoxy)propane. Step 1: To a 3-neck 500 mL round bottom flask equipped with a dry ice condenser, magnetic stir bar, and temperature probe was added KF (23.5 g, 405 mmol). The reaction vessel was then evacuated and backfilled with nitrogen three times before charging with tetraglyme (225 mL). The stirring mixture was cooled to an internal temperature of -10⁰C and was then charged with perfluoropropionyl fluoride (65.1 g, 392 mmol). At the same temperature, CF₂HCF₂CH₂ONf (172 g, 415 mmol) was then slowly added over the course of 30 minutes. After slowly warming to room temperature during an overnight stir, the resultant reaction mixture was diluted with water (100 mL), transferred to a 1 L separatory funnel, and then diluted with an additional portion of water (300 mL). Removal of the aqueous layer yielded 147 g of a crude fluorochemical mixture for which GC-FID analysis indicated formation of 1,1,1,2,2,3,3-heptafluoro-3-(2,2,3,3-tetrafluoropropoxy)propane (75% uncorrected GC yield). Fractional distillation of the crude fluorochemical mixture produced 1,1,1,2,2,3,3-heptafluoro-3-(2,2,3,3-tetrafluoropropoxy)propane (81⁰C, 740 mm/Hg) as a colorless liquid (71 g, 60% isolated yield). The purified material was used in the next step. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR. Step 2: To a 2-neck round bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe were charged KOH (9.9 g, 150 mmol), TBPBr (10.1 g, 30.0 mmol), and H₂O (25 mL). With stirring, KOH and TBPBr were dissolved completely before the addition of 1,1,1,2,2,3,3-heptafluoro-3-(2,2,3,3-tetrafluoropropoxy)propane (15.0 g, 50.0 mmol). The reaction mixture was stirred vigorously for 3 h at elevated temperature (80⁰C). A distillation head was then attached to one of the flask necks and the reflux condenser was removed. The temperature was increased until fluorochemical distillate was observed which co-distilled with some water. The aqueous layer was removed leaving 12.2 g of a fluorochemical distillate for which GC-FID analysis indicated complete conversion of starting material and formation of 1,1,1,2,2,3,3-heptafluoro-3- (2,3,3-trifluoroprop-1-enoxy)propane (72% uncorrected GC yield). Purification of the fluorochemical mixture via fractional distillation produced 1,1,1,2,2,3,3-heptafluoro-3- (2,3,3-trifluoroprop-1-enoxy)propane (84⁰C, 740 mm/Hg) as a colorless liquid (9.3 g, 66% isolated yield), Example 11. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR.

Example 12: Preparation of 1,1,2,2,3,3,4,4-octafluoro-5-(2,3,3-trifluoroprop-1- enoxy)cyclopentane. Step 1: A round-bottom 3-neck flask equipped with a magnetic stir bar, reflux condenser, and temperature probe was charged with KF (12.7 g, 219 mmol). The reaction vessel was evacuated and backfilled with nitrogen three times before the addition of tetraglyme (100 mL). The resultant mixture was then cooled (0⁰C) with stirring followed by the slow addition of perfluorocyclopentanone (50.0 g, 219 mmol) over the course of 10 min. When the resultant mixture had cooled back to 0⁰C, CF₂HCF₂CH₂ONf (90.8 g, 219 mmol) was slowly added over the course of 10 minutes and the resultant reaction mixture was allowed to slowly rise to room temperature during an overnight stir. The resultant mixture was then diluted by the addition of water (50 mL), transferred to a separatory funnel, and then further diluted by water (950 mL). Removal of the aqueous phase yielded 84.5 g of a fluorochemical mixture for which GC-FID indicated formation of 1,1,2,2,3,3,4,4,5-nonafluoro-5-(2,3,3-trifluoropropoxy)cyclopentane (92% uncorrected GC-FID yield). Fractional distillation of the fluorochemical mixture produced 1,1,2,2,3,3,4,4,5-nonafluoro-5-(2,3,3-trifluoropropoxy)cyclopentane (119⁰C, 740 mm/Hg) as a colorless liquid (59.3 g, 78% isolated yield). Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR. Step 2: To a 2-neck round bottom flask equipped with a magnetic stir bar, reflux condenser, and temperature probe were charged KOH (11.5 g, 174 mmol), TBPBr (9.8 g, 29.1 mmol), and H₂O (25 mL). With stirring, KOH and TBPBr were dissolved completely before the addition of 1,1,2,2,3,3,4,4,5-nonafluoro-5-(2,3,3-trifluoropropoxy)cyclopentane (20.0 g, 58.1 mmol). The reaction mixture was stirred vigorously for overnight at elevated temperature (80⁰C). A distillation head was then attached to one of the flask necks and the reflux condenser was removed. The temperature was increased until fluorochemical distillate was observed which co-distilled with some water. The aqueous layer was removed leaving 14.1 g of a fluorochemical distillate for which GC-FID analysis indicated complete conversion of starting material and formation of 1,1,2,2,3,3,4,4-octafluoro-5- (2,3,3-trifluoroprop-1-enoxy)cyclopentane as a colorless liquid (75% isolated yield), Example 12. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR.

Comparative Example 1 (CE-1). Attempted dehydrofluorination of 1,1,1,2,2,4,4,4- octafluoro-3-(2,2,2-trifluoroethoxy)-3-(trifluoromethyl)butane. Step 1: A 600 mL stainless steel pressure reactor was charged with KF (16.1 g, 277 mmol), 18-Crown-6 (10.5 g, 39.7 mmol), and tetraglyme (100 mL). The reaction vessel was sealed and evacuated under reduced pressure followed by the slow addition of 2,2,3,3,3-pentafluoropropionyl fluoride (43.0 g, 259 mmol) to the stirring mixture via a PTFE line. TMSCF₃ (77.3 g, 544 mmol) was then slowly added via a PTFE line over the course of 1 h to avoid temperature increases above 45⁰C. The resultant reaction mixture was stirred overnight at room temperature. The mixture was then transferred to a 3-neck round bottom flask equipped with a temperature probe and magnetic stir bar. With stirring, the TMS-F by-product was removed by sweeping the headspace over the heated (60⁰C) reaction mixture with a steady stream of N₂. The mixture was then allowed to cool to room temperature and was used for the next step without further purification. Step 2: Half of the mixture from step 1 was transferred to a 3-neck round bottom flask equipped with a temperature probe, reflux condenser, and magnetic stir bar. To the stirring, heated (60⁰C) mixture, CF₃CH₂OTf (30.5 g, 130 mmol) was slowly added. After an overnight stir at the same temperature, the resultant mixture was allowed to cool to room temperature and was then diluted by the addition of water (150 mL). After transferring to the separatory funnel, the aqueous phase was removed yielding a crude fluorochemical mixture for which GC-FID analysis indicated approximately 97% conversion of the CF3CH2OTf. Fractional distillation of the crude fluorochemical mixture produced 1,1,1,2,2,4,4,4-octafluoro-3-(2,2,2-trifluoroethoxy)-3-(trifluoromethyl)butane (91⁰C, 740 mm/Hg) as a colorless liquid (29.2 g, 61% isolated yield). The purified material was used in the next step. Confirmation of the chemical compound was obtained by conventional proton and fluorine NMR. Step 3: A 20 mL glass vial equipped with a magnetic stir bar was charged with KOH (0.36 g, 5.4 mmol), water (0.50 mL), TBACl (0.076 g, 0.27 mmol), and 1,1,1,2,2,4,4,4-octafluoro-3-(2,2,2-trifluoroethoxy)-3-(trifluoromethyl)butane (1.0 g, 2.7 mmol). The resultant mixture was stirred at 80⁰C for 16 hours. GC-FID analysis of the crude reaction mixture indicated no conversion of 1,1,1,2,2,4,4,4-octafluoro-3-(2,2,2- trifluoroethoxy)-3-(trifluoromethyl)butane starting material.

Comparative Example 2 (CE-2): Preparation of 1,3,3,3-tetrafluoro-N-(perfluoroethyl)-N- (trifluoromethyl)prop-1-en-1-amine. CE-2 was prepared as described in U.S. Pat. Publ. 2018/0141893, which is incorporated herein by reference in its entirety, Example 1. Comparative Example 3 (CE-3): 3,3,4,4,5,5,6,6,6-nonafluorohex-1-ene. CE-3 was purchase from Synquest Laboratories, Inc., and used as received. Comparative Example 4 (CE-4): 3,3,4,4,5,5-hexafluorocyclopent-1-ene. CE-4 was purchase from Synquest Laboratories, Inc., and used as received. Comparative Example 5 (CE-5): (Z)-1,1,1,4,4,4-hexafluorobut-2-ene. CE-5 was purchase from Synquest Laboratories, Inc., and used as received. Dielectric Constants of Examples 1, Example 3 and CE-2 through CE-5 The dielectric constant was determined using ASTM D150 with the average value reported at 1 KHz. Dielectric constant values were measured for Example 1, Example 3, CE-2, CE-3, CE-4, and CE-5. The dielectric constants presented in Tables 1 and 2, below, were measured using a broadband Dielectric Spectrometer available from Novocontrol Technologies, GmbH, Montabaur, Germany, per ASTM D150-11. The low dielectric constant data of Examples 1 and 3 demonstrates the compatibility of hydrofluoroolefin fluids of the present disclosure for high voltage applications. The results are surprising since similar hydrofluoroolefin structures (e.g., CE-2 – CE-5) show higher dielectric constant values. Table 1. Dielectric Example Chemical Structure Chemical Name z

Table 2. Comparativ Dielectric Chemical Structure Chemical Name

approximately 45 days from its rate of reaction with hydroxyl radicals. The pseudo-first order rate for the reaction of the gaseous 2,3,3,4,4,4-hexafluoro-1-(perfluoropropoxy)but- 1-ene with hydroxyl radical was measured in a series of experiments relative to reference compounds such as chloromethane and ethane. The measurements were performed in a 5.7 L, heated FTIR gas cell equipped with a polished semiconductor-grade quartz window. An Oriel Instruments UV Lamp, Model 66921 equipped with a 480W mercury-xenon bulb was used to generate hydroxyl radicals by photolyzing ozone in the presence of water vapor. The concentrations of 2,3,3,4,4,4-hexafluoro-1-(perfluoropropoxy)but-1-ene and the reference compound were measured as a function of reaction time using an I-Series FTIR from Midac Corporation. The atmospheric lifetime was calculated from the reaction rates for 2,3,3,4,4,4-hexafluoro-1-(perfluoropropoxy)but-1-ene relative to the reference compounds and the reported lifetime of the reference compounds as shown below: where ^_x is the atmospheric lifetime

4-hexafluoro-1-(perfluoropropoxy)but-1- ene, ^r is the atmospheric lifetime of the reference compound, and kx and kr are the rate constants for the reaction of hydroxyl radical with the test compound and the reference compound, respectively. Global Warming Potential (GWP): A measured IR cross-section was used to calculate the radiative forcing value for Example 3 (2,3,3,4,4,4-hexafluoro-1- (perfluoropropoxy)but-1-ene) using the method of Pinnock et al. as described in J. Geophys. Res. 1995, 100, 23227–23238. The GWP (100-year iterative time horizon ĨITH)) is calculated using the radiative forcing value and the experimentally determined atmospheric lifetime. A GWP value of 5 was determined.

Claims

What is claimed is: 1. A hydrofluoroolefin ether compound represented by the following general formula (I): wherein Rf¹ is a linear, branched, or

lkyl group containing 1-5 carbon atoms and may contain up to 2 H atoms; Rf² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; R_f ³ is an F atom, a CF₃ group, or a CF₂CF₃ group; or R_f ² and R_f ³ together form a perfluorinated ring structure with 5-6 carbon atoms; R_f ⁴ is an F atom, a CF₃ group, or a CF₂CF₃ group. 2. The hydrofluoroolefin ether compound of claim 1, wherein R_f ¹ is a linear fluoroalkyl group containing 1-5 carbon atoms. 3. The hydrofluoroolefin ether compound of claim 1, wherein Rf¹ is a linear fluoroalkyl group containing 1-5 carbon atoms and containing 1 H atom. 4. The hydrofluoroolefin ether compound of claim 1, wherein R_f ² is a perfluorinated alkyl group containing 1-3 carbon atoms; and R_f ³ and R_f ⁴ each is an F atom. 5. The hydrofluoroolefin ether compound of claim 1, wherein R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; R_f ³ is a CF₃ group, or a CF₂CF₃ group; or R_f ² and R_f ³ together form a perfluorinated ring structure with 5-6 carbon atoms; and R_f ⁴ is an F atom. 6. The hydrofluoroolefin ether compound of claim 1, wherein R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; R_f ³ is a CF₃ group, or a CF₂CF₃ group; and R_f ⁴ is a CF₃ group, or a CF₂CF₃ group. 7. The hydrofluoroolefin ether compound of claim 1, comprising a structure selected from:

8. A working fluid comprising a hydrofluoroolefin ether compound represented by the following general formula (I):

wherein R_f ¹ is a linear, branched, or cyclic fluoroalkyl group containing 1-5 carbon atoms and may contain up to 2 H atoms; R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; R_f ³ is an F atom, a CF₃ group, or a CF₂CF₃ group; or R_f ² and R_f ³ together form a perfluorinated ring structure with 5-6 carbon atoms; R_f ⁴ is an F atom, a CF₃ group, or a CF₂CF₃ group; wherein the hydrofluoolefin ether compound is present in the working fluid at an amount of at least 25% by weight based on the total weight of the working fluid. 9. The working fluid of claim 8, wherein the working fluid comprises a heat transfer fluid, a coating solvent, a foam blowing agent, an electrolyte solvent, an additive for lithium-ion batteries, or a cleaning fluid. 10. A method of making a hydrofluoroolefin ether comprising: providing a perfluorinated precursor compound comprising: a perfluorinated acid fluoride with general structure: R_f ²- (CO)-F wherein R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; (CO) is a carbonyl group C=O; or a perfluorinated ketone with general structure: R_f ²- (CO)-R_f ³ wherein R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; R_f ³ is a CF₃ group, or a CF₂CF₃ group; or R_f ² and R_f ³ together form a perfluorinated ring structure with 5-6 carbon atoms; (CO) is a carbonyl group C=O; reacting the perfluorinated precursor with a reaction mixture comprising a fluoride salt comprising a metal fluoride salt or a tetraalkylammonium fluoride salt, in an aprotic organic solvent, to form a fluorinated alkoxide salt; quenching the fluorinated alkoxide salt with an electrophile Rf¹-CF2-CH2-X wherein R_f ¹ is a linear, branched, or cyclic fluoroalkyl group containing 1-5 carbon atoms and may contain up to 2 H atoms; and X is -OSO₂CF₃, -OSO₂CF₂CF₃, or -OSO₂CF₂CF₂CF₂CF₃; to form a fluorinated compound of general Formula II: wherein R_f ¹ is a linear, branched, or cyclic fluoroalkyl group containing 1-5 carbon atoms and may contain up to 2 H atoms; R_f ² is a perfluorinated alkyl group containing 1-6 carbon atoms and may contain one or more catenated heteroatoms selected from O or N; R_f ³ is an F atom, a CF₃ group, or a CF₂CF₃ group; or R_f ² and R_f ³ together form a perfluorinated ring structure with 5-6 carbon atoms; and R_f ⁴ is an F atom, a CF₃ group, or a CF₂CF₃ group; and dehydrofluorination with an aqueous solution of a metal hydroxide and a phase transfer catalyst to form a hydrofluoroolefin ether of general Formula I: wherein Rf¹, Rf², Rf³, and Rf⁴ are as

11. The method of claim 10, wherein the reaction mixture comprising a fluoride salt and an aprotic organic solvent, further comprises tetrafluoroethylene (TFE) or perfluoroalkyltrimethyl silane. 12. The method of claim 10, wherein the fluorinated compound of general Formula II is selected from: