CN111909209A

CN111909209A - Preparation method of biphenyl tetradentate phosphonite ligand

Info

Publication number: CN111909209A
Application number: CN202010794422.6A
Authority: CN
Inventors: 张润通; 彭江华; 王建新; 闫鑫
Original assignee: Huizhou Kailisi Technology Co ltd
Current assignee: Huizhou Kailisi Technology Co ltd
Priority date: 2020-08-10
Filing date: 2020-08-10
Publication date: 2020-11-10

Abstract

The invention discloses a novel biphenyl tetradentate phosphite ligand 2,2 ', 6, 6' -tetra [ (1,1 '-biphenyl-2, 2' -diyl) phosphonite]A preparation method of (E) -3,3 ', 5,5 ' -tetra-tert-butyl-1, 1 ' -biphenyl and derivatives thereof. The novel biphenyl tetradentate phosphonite ligand has a structure shown as a general formula I, wherein a substituent R in the general formula I can be a cyclic phosphine structure. The novel biphenyl tetradentate phosphonite ligand has better conversion rate and normal-iso ratio in a mixed/etherified carbon tetra (butylene) hydroformylation reaction system.

Description

Preparation method of biphenyl tetradentate phosphonite ligand

Technical Field

The invention relates to a preparation method of a novel biphenyl

tetradentate phosphonite ligand

2,2 ', 6,6 ' -tetra [ (1,1 ' -biphenyl-2, 2 ' -diyl) phosphonite ] -3,3 ', 5,5 ' -tetra-tert-butyl-1, 1 ' -biphenyl and derivatives thereof.

Background

Hydroformylation has found a very large industrial application since 1938 in professor Otto Roelen (Chem abstract, 1994, 38-550). Since aldehydes can be very easily converted into corresponding alcohols, carboxylic acids, esters, imines, and the like, which have important uses in organic synthesis, aldehydes synthesized by hydroformylation are synthesized on a large scale in industrial production. Aldehydes produced by hydroformylation in industrial production per year now reach 1000 ten thousand tons (adv. synth. catal.2009,351, 537- & 540).

In hydroformylation reactions, while bidentate and tetradentate phosphine ligands have been widely reported and patented by foreign large chemical companies such as BASF, Dow, Shell and Eastman and some research groups, multidentate phosphine ligands have rarely been reported (Org. Lett.2013,15,1048-. Therefore, the development of a novel efficient tetradentate phosphine oxide ligand and a preparation method thereof in the hydroformylation reaction have important significance.

Phosphites are industrially used mainly for antioxidants, heat stabilizers, flame retardants and the like in polymer materials such as plastics, rubbers and the like. It is a phosphorous acid hydroxy derivative, which can be classified into phosphorous acid monoester ROP (OH) according to the number of hydroxy groups in the molecule₂Phosphorous acid diester (RO)₂POH and Triphosphite (RO)₃And P. The hydroxyl or alkoxy group is substituted with a halogen atom to form a halophosphite. Among the halophosphites, chlorophosphite is the most important intermediate of trivalent organophosphorus compounds. The most common method for industrially preparing phosphite ester is direct esterification, which means that halogenated material of trivalent phosphorus is used as raw material to react with alcohol by controlling certain reaction conditions.

Propylene is used as a raw material, and butyraldehyde which is a hydroformylation reaction product of the propylene is subjected to a series of reactions such as aldol condensation, hydrogenation and the like to obtain a plasticizer dioctyl phthalate (DEHP) which is widely applied in industry. DEHP yields in china are higher than 300 ten thousand tons per year, while annual yields in the world are as high as 1000 ten thousand tons. However, the price of propylene raw materials is increasing year by year, and the plasticizer DEHP has small molecular weight, is cracking and volatile, has large toxicity to human bodies, and has been prohibited from production and recycling by REACH regulation listed in European Union in 2015. Current improvement the current improved process is by mixing/ethersThe hydroformylation of the butene is carried out to obtain valeraldehyde, and the high molecular weight novel plasticizer DPHP is produced through similar subsequent reactions. DPHP is not easily cracked and has low toxicity. At present, the technology is expected to gradually replace the traditional technology. Traditionally based on PPh₃The technology can only realize the hydroformylation of 1-butene, the production cost of 1-butene is high, and the cheaper raw material is mixed butene or butene after ether. The domestic hydroformylation industrial device mainly uses PPh₃And bidentate phosphonite ligands (Biphephos) used in Dow Chemical (Dow Chemical) are dominant. With foreign catalysts and processes, in addition to the high royalties and process package transfer costs that must be paid, the Biphephos ligand of dow chemistry is unstable in air for a long time, is easily hydrolyzed, acidolyzed and tends to block pipelines, and sporadically added ligands are required to ensure catalytic activity.

Compared with the bidentate phosphonite ligand Biphephos, the preparation of the biphenyl tetradentate phosphonite ligand and the derivative thereof developed by the invention has the characteristics of easy synthesis, amplified synthesis, high yield, good reaction activity, high yield of straight-chain aldehyde products, extremely stable water and oxygen, difficult decomposition and the like. Meanwhile, through preliminary industrial small-scale research and comparison of Biphephos and other bidentate phosphine ligands, the novel biphenyl tetradentate phosphonite ligand developed by the invention can realize higher conversion rate, higher normal-iso ratio and better activity and stability in the hydroformylation reaction of mixed/etherified C4, and has great potential and practical value.

Disclosure of Invention

The invention aims to develop a high-efficiency synthesis method of biphenyl tetradentate phosphonite ligands and derivatives thereof. It is especially easy to synthesize, high in yield and capable of being synthesized in large scale. The structures of the compound and its derivatives are shown below:

in formula I, R can be a cyclic phosphine structure of phosphite ester, and is shown in the formula. The synthetic route of the biphenyl tetraphosphine ligand is as follows:

the synthetic route is as follows:

drawings

FIG. 1 shows a nuclear magnetic resonance hydrogen spectrum of a

compound

2,2 ', 6,6 ' -tetramethoxy-3, 3 ', 5,5 ' -tetra-tert-butyl-1, 1 ' -biphenyl (¹H NMR)；

FIG. 2 shows the NMR spectrum of ligand L1: (¹H NMR)；

FIG. 3 shows the phosphine nuclear magnetic resonance spectrum of ligand L1: (³¹P NMR)；

FIG. 4 is a high resolution mass spectrum (UPLC APCI-TOF-MS) of ligand L1:

FIG. 5 is a high resolution isotope resolution mass spectrum (UPLC APCI-TOF-MS) of ligand L1.

Detailed Description

The above route of the present invention is described in detail by the following examples, which should be noted that the present invention is only for further illustration and not limited to the present invention. Those skilled in the art can make insubstantial modifications and adaptations to the present invention.

Example 1

Preparation of 2,2 ', 6,6 ' -tetramethoxy-1, 1 ' -biphenyl:

1(13.8g), THF (200mL), tetramethylethylenediamine (16 g) were added to a 1L three-necked flask in this order, and n-butyllithium (40mL, 2.5mol/L) and then iron chloride (16.1g) were added under argon cooling at-78 ℃. The solvent was spin dried under reduced pressure, 400mL of water was added, and the mixture was extracted three times with ethyl acetate (500 mL each). The obtained organic phase is dried by anhydrous sodium sulfate, then is decompressed and dried by spinning, and the residue is subjected to flash column chromatography to obtain 22g of target product with the yield of 80%.

Example 2

Preparation of 2,2 ', 6,6 ' -tetrahydroxy-1, 1 ' -biphenyl:

in a 1L four-necked round-bottomed flask, 2(27g) and 500mL of methylene chloride were sequentially added, and after completion of the addition, boron tribromide (101g) was dropped into the flask at-30 ℃ to raise the temperature of the resulting reaction system to 30 ℃ for 4 hours. The resulting reaction mixture was concentrated, 400mL of water was added, and the mixture was extracted three times with ethyl acetate (600 mL each). The residue was subjected to column chromatography to obtain 20.5g of the target product at a yield of 91%.

Example 3

Preparation of 2,2 ', 6,6 ' -tetramethoxy-3, 3 ', 5,5 ' -tetra-tert-butyl-1, 1 ' -biphenyl:

a dry 1L Schlenk flask was charged with 3(22.0g), the flask was replaced with a nitrogen atmosphere, and 200mL of tetrahydrofuran, organic or inorganic acid (1.0g) was added at 25 ℃. The reaction was continued for 12 hours with continued introduction of 1.5 atmospheres of isobutene. After the reaction solution was quenched with water, 300mL of water was added and extracted three times with ethyl acetate (400 mL each). The obtained organic phase is dried by anhydrous sodium sulfate and then is dried by decompression and spin-drying to obtain a light yellow solid, and the column chromatography is carried out to obtain 40.0g of a target product with the yield of 90 percent.¹H NMR(600MHz, (CD₃)₂SO):＝7.53(s,4H),7.17(s,2H),1.37(s,36H)。

Example 4

Preparation of 1,1 '-biphenyl-2, 2' -dioxychlorophosphine:

20g of 2, 2' -biphenol was added to an excess of PCl₃In the middle, heating and refluxingAfter 6 hours, excess PCl was removed by distillation under reduced pressure₃18g of 7 are obtained as yellow oil in 71% yield.

Example 5

Preparation of 2,2 ', 6,6 ' -tetrakis [ (1,1 ' -biphenyl-2, 2 ' -diyl) phosphonite ] -3,3 ', 5,5 ' -tetra-tert-butyl-1, 1 ' -biphenyl (scheme 1):

4.2g of 2,2 ', 6,6 ' -tetrahydroxy-3, 3 ', 5,5 ' -tetra-tert-butyl-1, 1 ' -biphenyl and 100mL of anhydrous tetrahydrofuran were sequentially added to a 2L Schlenk flask under nitrogen protection, and 15 mL of 2.5M n-butyllithium was added dropwise at-78 ℃. The reaction mixture was warmed to room temperature and refluxed for 1 hour. Then, the reaction solution was dropped into 100mL of an anhydrous tetrahydrofuran solution of 1, 1' -dioxyphosphorochloridite (13g) at-78 ℃ and reacted at room temperature for 24 hours after completion of the dropping, the reaction solution was concentrated under a nitrogen atmosphere, and the residue was subjected to column chromatography to obtain 6.0g of the objective product with a yield of 46%.¹H NMR (400MHz,CDCl₃):＝7.74(s,2H),7.48–7.38(m,8H),7.19(td,J＝7.6,7.2,2.2 Hz,8H),7.11(dd,J＝6.5,1.7Hz,16H),1.30(s,36H)。³¹P NMR(243MHz,CDCl₃): ＝140.62。APCI-TOF/MS:Calculated for C₇₆H₇₁O₁₂P₄[M+H]⁺:1299.3818；Found: 1299.3891。

It is to be noted here that other biphenyl-type tetradentate phosphine ligands of L2-L26 of formula I can be prepared by using only different aryl-substituted phosphonium chloride derivatives as described in example 5.

Claims

1. A method for preparing novel biphenyl tetradentate phosphite ligand and derivatives thereof is characterized by comprising the following synthetic routes:

wherein, the structure of the novel biphenyl tetradentate phosphite ligand represented by the general formula I is as follows:

2. the method for preparing a novel biphenyl tetradentate phosphite ligand and its derivatives as claimed in claim 1, wherein the skeletal synthesis is carried out by the following reaction.

Preparation of 2,2 ', 6,6 ' -tetramethoxy-1, 1 ' -biphenyl.

3. The method for preparing a novel biphenyl tetradentate phosphite ligand and its derivatives as claimed in claim 1, wherein the skeletal synthesis is carried out by the following reaction.

Preparation of 2,2 ', 6,6 ' -tetrahydroxy-1, 1 ' -biphenyl.

4. The method for preparing a novel biphenyl tetradentate phosphite ligand and its derivatives as claimed in claim 1, wherein the skeletal synthesis is carried out by the following reaction.

Preparation of 2,2 ', 6,6 ' -tetramethoxy-3, 3 ', 5,5 ' -tetra-tert-butyl-1, 1 ' -biphenyl

The acid used in the above reaction may be one or more of an organic acid such as: formic acid, acetic acid, oxalic acid, dichloroacetic acid, trifluoroacetic acid, propionic acid, malonic acid, pyruvic acid, butyric acid, valeric acid, caproic acid, adipic acid, benzoic acid, p-nitrobenzoic acid, terephthalic acid, benzenesulfonic acid, fluorosulfonic acid, methanesulfonic acid, trifluoromethanesulfonic acid, p-toluenesulfonic acid, and the like; inorganic acids such as: hydrobromic acid, hydrochloric acid, hydrofluoric acid, sulfurous acid, sulfuric acid, perchloric acid, phosphonic acid, pyrophosphoric acid, nitric acid, nitrous acid, chromic acid, fluoroantimonic acid, and the like.

5. The process for the preparation of the novel biphenyl tetradentate phosphonite ligands and their derivatives as claimed in claim 1, characterized in that the skeletal synthesis is carried out by the following reaction.

Route 1：

Route 2：

Preparation of 2,2 ', 6,6 ' -tetrakis [ (1,1 ' -biphenyl-2, 2 ' -diyl) phosphonite ] -3,3 ', 5,5 ' -tetra-tert-butyl-1, 1 ' -biphenyl (L1)

Meanwhile, the ether solvent used in the above reaction may be any one of tetrahydrofuran, diethyl ether, 2-methyltetrahydrofuran or dioxane.

6. A novel process for the stepwise substitution of bidentate phosphine ligands (e.g., Biphephos) using novel biphenyl tetradentate phosphonites as ligands in mixed/ethereal hydroformylation reactions. The process is characterized in that the novel biphenyl tetradentate phosphonite ligands used may be as described in claim 1 having the general formula I.

7. A novel process as claimed in claim 6, wherein novel biphenyltetradentate phosphonites are used as ligands in mixed/ethereal carbohydroformylation and for stepwise substitution of bidentate phosphine ligands (e.g.Biphephos). The method is characterized by being realized according to the following process steps and parameters.

(1) Under the protection of inert gas, adding a certain proportion of novel biphenyl tetradentate phosphonite ligand and rhodium catalyst in a reaction device in sequence, wherein the molar ratio of phosphine to rhodium is about 1-5: 1, and stirring and complexing for 30 minutes at room temperature under an organic solvent.

(2) Then, under the protection of inert gas, under the switching of a two-position four-way valve, adding a certain proportion of liquid mixed C-C or C-C or cis-2-butene or trans-2-butene into the reaction kettle by using a plunger pump with a metering function, controlling the concentration of the rhodium catalyst to be about 50-200 ppm, and uniformly stirring at room temperature for 5-10 minutes.

(3) After stirring uniformly, filling CO and H with a certain pressure into the reaction device₂The pressure ratio of hydrogen to carbon monoxide is between 1:1 and 1:5, and the total pressure is between 0.5MPa and 1 MPa; and stirring and reacting for 1-4 hours at the temperature of 40-80 ℃.

8. The reaction process according to claim 7,

the carbon four after the carbon four and the ether are mixed is as follows: mixing C-IV (1-butene (25 wt%), cis-2-butene (40 wt%) and trans-2-butene (35 wt%), C-IV after ether (isobutane (52.1 wt%), 1-butene (16.6 wt%), cis-2-butene (15.3 wt%) and trans-2-butene (16.0 wt%)), wherein the contents of the cis-2-butene and the trans-2-butene are more than 98.0 wt%;

or the organic solvent is any one of toluene, dichloromethane, dichloroethane, hexane, ethyl acetate, dioxane, tetrahydrofuran or n-valeraldehyde.