WO1995021606A1

WO1995021606A1 - 2,2,4-trimethyl-penten-1-yl compounds, fragrance and flavor compositions

Info

Publication number: WO1995021606A1
Application number: PCT/US1994/001408
Authority: WO
Inventors: Roger J. H. Duprey; Benjamin O. Isaac
Original assignee: Union Camp Corporation
Priority date: 1994-02-08
Filing date: 1994-02-08
Publication date: 1995-08-17

Abstract

The present invention relates to 2,2,4-trimethyl-penten-1-yl compounds of formulas (I) and (II) wherein each R is, independently, H, or a substitued or unsubstituted C1-C6 alkyl, C2-C6 alkenyl, C6-C12 aryl, or C7-C18 alkylaryl, in particular 2,2,4-trimethyl-pent-3-en-1-yl isobutyrate and 2,2,4-trimethyl-pent-4-en-1-yl isobutyrate, and their use in novel fragrance and flavor compositions.

Description

,2,4-TRIMETHYL-PENTEN-l-YLCOMPOUNDS,FRAGRANCEANDFLAVORCOMPOSITIONS

BACKGROUND 07 THE INVENTION

The present invention relates to the field of fragrance and flavor additives, and more specifically to the use of 2,2,4-trimethyl-penten-l-yl compounds as fruity, floral fragrances and flavorants.

Synthetic chemical compounds which can provide a fruity, floral aroma are of great importance to the perfumery industries. Many of the natural materials which impart such fragrances to perfume compositions are often expensive and of variable quality. Such natural materials are also, at times, unavailable. Accordingly, great efforts have been made to find synthetic substitutes for such natural materials. Unfortunately, many of these efforts have resulted in compounds which possess only a very small degree of fragrance character, or contribute an undesired odor to the compositions.

New and/or better fruity and/or floral flavor and fragrance compounds are needed. The present invention is directed to these important ends. SUMMARY OF THE INVENTION

The present invention provides novel fragrance and flavor compositions comprising compounds of the formulas

[I] and

[II]

wherein each R is, independently, H, or a substituted or unsubstituted C_a-C₈ allcyl, C₂-C₆ allcenyl, C₆-C₁₂ aryl, or

C₇-C₁₈ alkylaryl.

The compounds of formulas [I] and [II] , collectively referred to herein as 2,2,4-trimethyl- penten-1-yl compounds, have active fruity, floral flavor and fragrance characteristics, making them extremely useful in fragrance and/or flavor compositions. DETAILED DESCRIPTION OF THE INVENTION

As noted above, the 2,2,4-trimethyl-penten-l-yl compounds of the invention include the compounds of the formulas

[I]

(a 2,2,4-trimethyl-pent-3-en-l-yl compound)

and

[II]

(a 2,2,4-trimethyl-pent-4-en-l-yl compound), wherein each R is, independently, H, or a substituted or unsubstituted C_j^-C alkyl, C₂-C₆ alkenyl, C₆-C₁₂ aryl, or C₇-C₁₈ alkylaryl. As used herein, the term "alkyl", used either alone or in compound words such as "alkylaryl", denotes straight chain or branched alkyls, such as for example methyl, ethyl, n-propyl, isopropyl or the different butyl, pentyl or hexyl isomers. As used herein, "alkenyl" denotes straight chain or branched alkenes, such as for example 1-propenyl, 2-propenyl, 3- propenyl, or the different butenyl, pentenyl or hexenyl isomers. As used herein, "aryl" denotes aryl groups such as for example, phenyl or naphthyl. By "substituted or unsubstituted", as used herein, it is meant that such compounds may be substituted with suitable substitutents, such as for example, OH.

In formulas [I] and [II], preferably R is an unsubstituted compound. Also, preferably R is an unsubstituted C₁-C₆ alkyl, more preferably an unsubstituted ^-^ alkyl, and most preferably an unsubstituted C₃ alkyl. Also preferably, the formula [I] compound is 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate, a compound of the specific formula

[III] and the formula [II] compound is 2,2,4-trimethyl-pent-4- en-l-yl isobutyrate, a compound of the specific formula

[IV] Most preferably, the compound is a formula [I] compound, especially 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate, a compound of the specific formula [III] .

Exemplary compounds with in the scope of formulas [I] and [II] include the following: • 2,2,4-trimethyl-pent-3-en-l-yl formate

(Formula [I] wherein R «= -H)

• 2,2,4-trimethyl-pent-4-en-l-yl formate (Formula [II] wherein R = -H)

• 2,2,4-trimethyl-pent-3-en-l-yl acetate (Formula [I] wherein R = -CH₃)

• 2,2,4-trimethyl-pent-4-en-l-yl acetate (Formula [II] wherein R = -CH₃)

• 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate (Formula [I] wherein R = CH,

-CH-CH₃ ) • 2,2,4-trimethyl-pent-4-en-l-yl isobutyrate (Formula [II] wherein R =

• 2,2,4-trimethyl-pent-3-en-l-yl tiglate (Formula [I] wherein R = -(CH₃)C=CHCH₃)

• 2,2,4-trimethyl-pent-4-en-l-yl tiglate (Formula [II] wherein R = -(CH₃)C=CHCH₃) • 2,2,4-trimethyl-pent-3-en-l-yl isovalerate

(Formula [I] wherein R - -CH₂CH(CH₃)₂)

• 2,2,4-trimethyl-pent-4-en-l-yl isovalerate (Formula [II] wherein R = -CH₂CH(CH₃)₂)

• 2,2,4-trimethyl-pent-3-en-l-yl salicylate (Formula [I] wherein R = -C₆H₄(OH))

• 2,2,4-trimethyl-pent-4-en-l-yl salicylate (Formula [II] wherein R - -C₆H₄(OH))

• 2,2,4-trimethyl-pent-3-en-l-yl benzoate (Formula [I] wherein R = -CgH₅) • 2,2,4-trimethyl-pent-4-en-l-yl benzoate

(Formula [II] wherein R - -C₆H₅)

The subject 2,2,4-trimethyl-penten-l-yl compounds are extremely stable, are relatively easy and inexpensive to prepare, and have a highly active fruity, floral flavor and fragrance characteristic, making them very desirable substitutes for the some of the natural compounds presently employed in fruity floral flavor or fragrance compositions.

The foregoing compounds of the invention can be efficiently prepared by methods well known to those skilled in the art, once armed with the present disclosure. Suitable methods include those described in U.S. Patent No. 3,408,388, issued October 29, 1968, and European Patent Application, Publication No. 0 305 965, published March 8, 1989, the disclosures of each of which are hereby incorporated herein by reference in their entirety.

In accordance with one suitable synthesis method, the 2,2,4-trimethyl-penten-l-yl compounds of the invention are prepared by catalytic dehydration of the corresponding saturated 2,2,4-trimethyl glycol monoesters, as described in U.S. Patent No. 3,408,388. Specifically, in accordance with the subject synthesis protocol, the monoesters may be contacted with a catalytic amount of a non-volatile acid catalyst at a reactor temperature of from about 100°C to about 180°C, preferably from about 110°C to about 160°C, although temperatures between about 100°C to about 270°C may be employed if desired. The saturated 2,2,4-trimethyl glycol monoester starting materials may also be prepared by conventional processes, such as by the trimeric condensation of the cr,α-disubstituted acetaldehydes, as described in U.S. Patent No. 3,091,632, issued May 28, 1963, the disclosures of which are hereby incorporated herein by reference in their entirety. Suitable acid catalysts include acid catalysts well known in the art, such as alkali metal hydrogen sulfates (e.g., sodium hydrogen sulfate and potassium hydrogen sulfate) , p- toluene sulfonic acid, sulfuric acid, and phosphoric acid. The amount of catalyst employed is generally from about 0.005 to about 5 weight percent, most preferably from about 0.1 to about 0.5 weight percent, based on the amount of saturated 2,2,4-trimethyl glycol monoester in the reactor. In accordance with one synthesis route, the compounds of the invention may be prepared by subjecting a saturated 2,2,4-trimethyl glycol monoester with a catalytic quantity of a highly acidic non-volatile compound, at temperatures between about 90°C to about 160°C, preferably between about 110°C and about 135°C, as described in U.S. Patent No. 3,408,388, the disclosures of which are hereby incorporated herein by reference in their entirety. The saturated 2,2,4-trimethyl glycol monoesters may be prepared by, for example, the trimeric condensation of a corresponding α-substituted aliphatic aldehyde in the presence of a basic catalyst (e.g., an alkali metal alkoxide) . Suitable highly acidic, non¬ volatile compounds include, for example, sulfuric acid, alkyl and aryl sulfates, alkyl and aryl sulfonic acids, phosphoric acid, alkyl and aryl phosphonates, alkyl and aryl phosphinic acids, pyrophosphoric acid, metaphosphoric acid and acetylsulfoacidic acid. Preferable of these compounds are sulfuric acid, p-toluenesulfonic acid, naphthalene sulfonic acid, phosphoric acid and pyrophosphoric acid. The amount of catalyst employed is generally from about 0.03 percent to about 3 percent by weight of the 2,2,4-trimethyl glycol monoester in the reactor. Preferably, the reaction is carried out in the presence of an inert diluent such as benzene, toluene, isobutyl isobutyrate, hexane, and cyclohexane. Thus, in accordance with this method, for example, 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate may be prepared by reacting 3-hydroxy-2,2,4-trimethylpentyl isobutyrate with p-toluenesulfonic acid in the presence of toluene at a reactor temperature of between about 120^βC and about 130°C.

The reaction can be carried out in any suitable vessel which provides sufficient contacting between the reactants. For simplicity, a stirred batch reactor can be employed. Glass lined vessels are suitable, as well as other vessels well-known in the art. The reagents may be added to the vessel in any order.

The pressure at which the reaction is carried out is not critical. If the reaction is carried out in a sealed vessel, autogenous pressure is acceptable, although higher or lower pressures, if desired, may be employed. The reaction may also be carried out at atmospheric pressure in an open reaction vessel. The reaction may take place in an oxygen atmosphere or an inert atmosphere, as in the presence of a gas such as nitrogen, argon and the like, the type of atmosphere also not being critical.

Reaction time is generally rather short and is often dictated by the type of equipment employed. Sufficient time should be provided, however, for thorough contacting of the reactants. Generally, the reaction proceeds to completion in about 0.5 to about 8 hours, most often in about 4 to about 5 hours.

The 2,2,4-trimethyl-penten-l-yl product can be recovered from the reaction mixture by conventional organic extraction techniques as will be readily apparent to those skilled in the art. Product of varying degrees of purity can then be obtained by subjecting the washed reaction mixture to fractional crystallization, reduced pressure fractional distillation, commercial chromatographic separation (for example, absorption chromotography, column chromotography, preparative gas chromotography, etc.), or other separation means well known to those skilled in the art.

The 2,2,4-trimethyl-penten-l-yl compounds of formulas [I] and [II], especially those of formulas [III] and [IV], with their powerful organoleptic properties, have high utility in the flavor and fragrance industry. In flavor formulations, they impart a powerful and very fine fruity, floral note. As a fragrance, they provide an active fruity, floral aroma. These compounds can be employed alone, in combination with one another, and/or in combination with one or more ingredients to provide excellent fruity, floral fragrance or flavor compositions. The compounds of the invention are particularly useful in rounding off compositions, and blend particularly well with aldehydes in various fragrance types.

For example, the compounds of formulas [I] and [II] may be used as olfactory components in anionic, cationic, nonionic and zwitterionic detergents, soaps, fabric softener compositions, fabric softener articles for use in clothes dryers, space odorants and deodorants, perfumes, colognes, toilet water, toiletries, bath preparations, deodorants, cosmetics, hand lotions, sunscreens, powders, as well as in other ways. The amount of the subject compounds to be used in modifying the olfactory or fragrance properties of a composition (that is, modifying, augmenting, enhancing, or improving the aroma of such compositions) , will vary depending upon the particular use intended, as will be readily apparent to those skilled in the art. Although they may be present in major or minor amounts, preferably, because of the strength of their odor, the compounds of the invention are generally employed as a minor ingredient, that is, in an amount of about 0.1 percent by weight of the fragrance composition up to about 50 percent by weight of the fragrance composition, preferably about 0.1 percent by weight up to about 30 percent by weight of the fragrance composition, and most preferably about 0.1 percent by weight up to about 5.0 percent by weight of the fragrance composition. Within these basic parameters, the olfactorily effective amount (that is, the amount of the compounds of formulas [I] and [II] effective to modify, augment, entrance or improve the aroma properties of a composition) will be well within the ambit of one skilled in the art, once armed with the present disclosures. The fragrance compositions of the invention may, if desired, contain a carrier or vehicle (as used herein, the term "carrier" shall be considered synonymous with the term "vehicle") . Such carriers include liquids such as a non-toxic alcohol, a non-toxic glycol, or the like. An example of a non-toxic alcohol is ethyl alcohol. An example of a non-toxic glycol is 1,2-propylene glycol. Alternatively, the carrier can be an absorbent solid such as a gum, e.g., gum arabic, xantham gum or guar gum, or components for encapsulating a composition such as gelatin, by means of coacervation or such as a urea formaldehyde polymer whereby a polymeric shell is formed around a liquid perfume oil center. The amount of the vehicle or carrier will vary depending upon the particular vehicle or carrier employed and use intended, as will be readily apparent to those skilled in the art. However, the vehicle or carrier can generally be employed in an amount of about 5 percent by weight up to about 95 percent by weight of the fragrance composition.

The fragrance composition may alternatively or additionally contain other perfumery materials. Typical additional perfumery materials which may form part of compositions of the invention include: natural essential oils such as lemon oil, mandarin oil, clove leaf oil, petitgrain oil, cedar wood oil, patchouli oil, lavandin oil, neroli oil, ylang oil, rose absolute or jasmine absolute; natural resins such as labdanum resin or olibanum resin; single perfumery chemicals which may be isolated from natural sources or manufactures synthetically, as for example, alcohols such as geraniol, nerol, citronellol, linalol, tetrahydrogeraniol, betaphenylethyl alcohol, methyl phenyl carbinol, dimethyl benzyl carbinol, menthol or cedrol; acetates and other esters derived from such alcohols; aldehydes such as citral, citronellal, hydroxycitronellal, lauric aldehyde, undecylenic aldehyde, cinna aldehyde, amyl cinnamic aldehyde, vanillin or heliotropin; acetals derived from such aldehydes; ketones such as methyl hexyl ketone, the ionones and the methylionones; phenolic compounds such as eugenol and isoeugenol; synthetic musks such as musk xylene, musk ketone and ethylene brassylate; and other materials commonly employed in the art of perfumery. Typically at least five, and usually at least ten, of such materials will be present as components of the active ingredient. Particularly preferred additional perfumery materials include hydroxycitronellal, decanal, geraniol, citronellol, indol, lilial, cardamon oil, lemon oil and phenyl ethyl alcohol. These latter perfumery materials will blend especially well with the compounds of formulas [I] and [II] to produce a fragrance composition having a particularly attractive odor. The amount of the additional perfumery material will vary depending upon the particular perfumery material employed and use intended, as will be apparent to those skilled in the art.

Fragrance compositions and preparatory techniques are well known in the art, and are disclosed, for example, in "Soap, Perfumery and Cosmetics", by W.A. Poucher, 7th edition, published by Chapman & Hall (London) (1959); "Perfume and Flavour Chemicals", by S. Arctander, published by the author (Montclair) (1959) ; and "Perfume and Flavour Materials of Natural Origin", also by S. Arctander, self-published (Elizabeth, NJ) (1960) , the disclosures of each of which are incorporated herein by reference, in their entirety.

The compounds of the invention can likewise be used as flavor ingredients in food and beverage compositions, as will be readily apparent to those skilled in the art. The amount of the subject compounds to be used in modifying the flavor properties of a composition (that is, modifying, augmenting, enhancing, or improving the flavor of such food or beverages compositions) , will vary depending upon the particular use intended, as will be readily apparent to those skilled in the art. Although they may be present in major or minor amounts, preferably, because of the strength of their flavor, the compounds of the invention are generally employed as a minor ingredient, that is, in an amount of about 0.1 percent by weight up to about 30 percent by weight of the flavored food or beverage composition, preferably about 0.1 percent by weight up to about 5.0 percent by weight of the flavored food or beverage composition. Within these basic parameters, the effective flavor modifying amount (that is, the amount of the compounds of formulas [I] and [II] effective to modify, augment, enhance or improve the flavor of a food or beverage composition) , will be well within the ambit of one skilled in the art, once armed with the present disclosures.

The flavor compositions of the invention may, if desired, contain a diluent, which may be any physiologic¬ ally safe solid or liquid material. Examples of suitable liquid diluents include water, edible oils, and polyhydric alcohols. Suitable solid diluents include carriers, vehicles, fillers, binders, extenders, bulking agents, thickening agents, and suspending agents, such as dextrans, lactose, whey solids and starch. These and other suitable diluents will be readily apparent to those skilled in the art, and are disclosed in numerous publications. The amount of the diluent will vary depending upon the particular diluent employed and use intended, as will be apparent to those skilled in the art. Flavored food and beverage compositions and preparatory techniques are also well known to those skilled in the art and are disclosed in numerous publications.

The present invention is further described in the following examples. These examples are not to be construed as limiting the scope of the appended claims.

EXAMPLES

Example 1

Preparation of 2,2, -Trimsth 1- Pent-3-en-l-yl Isobutyrate

This example illustrates the synthesis of 2,2,4- trimethyl-pent-3-en-l-yl isobutyrate (the compound of formula [III]) from 3-hydroxy-2,2,4-trimethyl-pentyl isobutyrate.

A mixture of 300 ml of toluene, 400 ml (376 g; 1.74 moles) of 3-hydroxy-2,2,4-trimethylpentyl- isobutyrate and 2 g of p-toluenesulfonic acid were charged into a reactor. The mixture was heated to refluxed temperature and refluxed for about 6 to 8 hours. During this time, the reaction temperature ranged from about 120^βC to about 130°C.

The reaction mixture was cooled, washed with dilute sodium carbonate and water, and distilled at reduced pressure, to obtain the desired 2,2,4-trimethyl- pent-3-en-l-yl isobutyrate compound.

EXAMPLE 2

Preparation of 2,2, -Trimsth 1- Pent-3-en-yl Acetate

This example illustrates the synthesis of 2,2,4- trimethyl-pent-3-en-l-yl acetate (the compound of formula [I] wherein R is CH₃) from 2,2,4-trimethyl-pentan-l,3- diol.

A solution of 2,2,4-trimethyl-pentan-l,3-diol (100 g) in toluene, containing acetic acid (42 g) and p- toluenesulfonic acid, was heated under reflux at 100°C, for about 6 to 7 hours. During this time any water was removed via azeotropic distillation. The reaction mixture was then cooled and washed with water, then with aqueous sodium carbonate, and again with water. After washing the organic layer free of acids, the product was isolated by fractional distillation, boiling point 45°C, at 2 torr. grawpl e 3

Fragrance Characteristics of

2,2, -Trimethyl-Pent-3-en-l-yl Isobutyrate

This example illustrates the testing of 2,2,4- trimethyl-pent-3-en-l-yl isobutyrate (the compound of formula [III]) for its fragrance characteristics.

The compound 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate, prepared in accordance with the procedures of Example 1, was tested for its fragrance character- istics by qualified fragrance testers. The compound was found to possess a citrus, natural fruity character, reminiscent of chamomile, orange peel, green astringent, floral and mandarin.

Example 4

Fragrance Formulation of

2,2, -Trimethyl-Pent-3-βn-l-yl Isobutyrate

This example illustrates the formulation of 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate (the compound of formula [III]) into a fragrance composition. The compound 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate was added to a number of additional compounds to prepare a fragrance composition as follows. The manufacturer of the various ingredients is noted, where appropriate, in abbreviated form, in parenthesis. Names and locations of the various manufacturers may be found in Table A.

Ingredient Amount Basil Oil Indian (BFC) 10

Bigarade Oxide (BBA) 5

Citral 850 (BBA) 16

Cumin Oil SAS 10% DPG (BBA) 8

Galbanu Substit. AP1044 (BBA) 3 Isotagetone (BBA) 8

Lemon Terpenes Distilled (BBA) 160

Linalyl Acetate (GIV) 275

Methyl Naphthyl Ketone (H & R) 5

Neryl Acetate (BBA) 180 Olibanum Oil SAS 10% DPG (BBA) 2

Petitgrain oil Paraguay (FDL) 80

Tagette Oil S. African 10% DPG (FDCS) 8

Triplal (IFF) 40

2,2,4-trimethyl-pent-3- en-l-yl isobutyrate 200 1000 Total Parts

The foregoing fragrance composition possessed citrus and floral characteristics. Example 5

Fragrance Formulation of

2,2, -Trimethyl-Pent-3-βn-l-yl Isobutyrate

This example illustrates the formulation of 2,2,4- trimethyl-pent-3-en-l-yl isobutyrate (the compound of formula [III]) into a fragrance composition.

The compound 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate was added to a number of additional compounds to prepare a fragrance composition as follows. The manufacturer of the various ingredients is noted, where appropriate, in abbreviated form, in parenthesis. Names and locations of the various manufacturers may be found in Table A.

Ingredient Amount Benzyl Acetate (LCUK) 120

Citronellene Lactone (BBA) 40 Ethyl Maltol 1% Benzyl Alcohol (PFI) 20 Hexyl Cinnamic Aldehyde (FIR) 300 Indole (GIV) 10 Linalol Pure (GIV) 200

Methyl Anthranilate (DAKSA) 10

2,2, -trimethyl-pent-3- en-l-yl isobutyrate 300

1000 Total Parts The foregoing fragrance composition possessed floral and fruity characteristics.

TABLE A

BHAGAT FINE CHEMICALS (BFC) 164 SITARAM PODDAR MARG BOMBAY 400 002

F C COPELAND AND SONS LTD (FDCS) COLANOL HOUSE 5 WESTFIELD STREET LONDON SE 18 5TL

DESTILERIAS ADRIAN & KLEIN SA (DAKSA) AVDA FELIPE KLEIN S/N 12580 BENICARLO ESPANA LEEK CHEM UK (LCUK)

COURTAULDS FIND CHEMICALS LEEKS WORKS MACCLESFIELD ROAD STAFFORDSHIRE ST13 8UZ FIRMENICH UK LTD (FIR) HAYES ROAD SOUTHALL MIDDLESEX UB2 5NN

FUERST DAY LAWSON LTD (FDL) ST CLARE HOUSE 30 - 33 MINORIES LONDON EC3N 1LN

GIVAUDAN AND COMPANY LTD (GIV) GODSTONE ROAD WHYTELEAFE

SURREY CR3 OYE

HARMANN AND REIMER LTD (H & R) FIELDHOUSE LANE MARLOW, BUCKS SL7 1NA INTERNATIONAL FLAVORS AND FRAGRANCES LTD (IFF) DUDDERY HILL HAVERHILL SUFOLK CB9 8LG

PFIZER LIMITED (PFI) PO BOX 24

RAMSGATE ROAD SANDWICH KENT CT13 9QZ Various modifications of the invention, in addition to those shown and described herein, will be apparent to those skilled in the art from the foregoing description. Such modification are also intended to fall within the scope of the appended claims.

Claims

CLAIMS What is claimed is:

1. A fragrance composition comprising at least one compound selected from compounds of the formulas

[I]

and

[II]

wherein each R is, independently, H, or a substituted or unsubstituted C^C_g alkyl, C₂-C₆ alkenyl, C₆-C_α2 aryl, or C₇-C₁₈ alkylaryl.

2. A fragrance composition of Claim 1 wherein R is an unsubstituted C₁-C₃ alkyl.

3. A fragrance composition of Claim 2 wherein R is an unsubstituted C₃ alkyl.

4. A fragrance composition of Claim 1 wherein the compound is a compound of formula [I].

5. A fragrance composition of Claim 4 wherein the compound is 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate.

6. A fragrance composition of Claim 1 wherein the compound is a compound of formula [II] .

7. A fragrance composition of Claim 6 wherein the compound is 2,2,4-trimethyl-pent-4-en-l-yl isobutyrate.

8. A fragrance composition of Claim 1 further comprising an additional perfumery material.

9. A fragrance composition of Claim 5 further comprising an additional perfumery material.

10. A fragrance composition of Claim 1 further comprising a carrier.

11. A fragrance composition of Claim 5 further comprising a carrier.

12. A flavor composition comprising at least one compound selected from the compounds of the formulas

[I] and

[II]

wherein each R is, independently, H, or a substituted or unsubstituted C_α-C₆ alkyl, C₂-C₆ alkenyl, C₆-C₁₂ aryl, or C₇-C₁₈ alkylaryl.

13. A flavor composition of Claim 12 wherein R is an unsubstituted C_j-C₃ alkyl.

14. A flavor composition of Claim 13 wherein R is an unsubstituted C₃ alkyl.

15. A flavor composition of Claim 12 wherein the compound is a compound of formula [I].

16. A flavor composition of Claim 15 wherein the compound is 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate.

17. A flavor composition of Claim 12 wherein the compound is a compound of formula [II] .

18. A flavor composition of Claim 17 wherein the compound is 2,2,4-trimethyl-pent-4-en-yl isobutyrate.

19. A flavor composition of Claim 12 further comprising a diluent.

20. A flavor composition of Claim 16 further comprising a diluent.

21. A method of modifying the olfactory properties of a composition comprising adding thereto an olfactorily effective amount of at least one compound selected from compounds of the formulas

[I]

and

[II]

wherein each R is, independently, H, or a substituted or unsubstituted C^C_g alkyl, C₂-C₆ alkenyl, C₆-C₁₂ aryl, or C₇-C₁₈ alkylaryl.

22. A method of Claim 21 wherein the compound is 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate.

23. A method of Claim 22 further comprising adding an additional perfumery material.

24. A method of Claim 23 further comprising adding a carrier.

25. A method of modifying the flavor of a food or beverage comprising adding thereto an effective flavor modifying amount of at least one compound selected from compounds of the formulas

[I]

and

[II] wherein each R is, independently, H, or a substituted or unsubstituted C^C alkyl, C₂-C₆ alkenyl, C₆-C₁₂ aryl, or C₇-C₁₈ alkylaryl.

26. A method of Claim 25 wherein the compound is 2,2,4-trimethyl-pent-3-en-l-yl isobutyrate.

27. A method of Claim 26 further comprising adding an additional perfumery material.

28. A method of Claim 27 further comprising adding a carrier.