Isobutyric acid ester compound having a carbonate group at the α-position and fragrance composition

Abstract

A fragrance composition containing a compound represented by formula (1) as an active ingredient. (In formula (1), R1 represents a C1-4 linear, branched, or cyclic alkyl group, and R2 represents a C1-6 linear, branched, or cyclic alkyl group.)

Description

[Technical field]

[0001] The present invention relates to an isobutyric acid ester compound having a carbonate group at the α-position and a fragrance composition. [Background technology]

[0002] It is known that isobutyric acid esters include compounds useful as flavorings. For example, Non-Patent Document 1 describes that various isobutyric acid esters are mainly used as flavors, and specifically, it describes that methyl isobutyrate is sweet apricot-like, propyl isobutyrate is heavy pineapple-like, butyl isobutyrate is fresh apple and banana-like, and isoamyl isobutyrate is sweet apricot and pineapple-like, all of which are flavor materials with a fruity aroma. Furthermore, Patent Document 1 discloses that linear or branched alkyl esters of α-alkoxyisobutyric acid having 4 to 12 carbon atoms are useful as isobutyric acid esters having a bond to oxygen at the α-position, and describes that normal hexyl α-ethoxyisobutyrate has a lavender-like odor.

[0003] On the other hand, there are also known substances that are isobutyric acid esters having a carbonate group at the α-position. For example, Non-Patent Document 2 discloses that ethyl α-(normal pentyloxycarbonyl)oxyisobutyrate and ethyl α-(normal butoxycarbonyl)oxyisobutyrate are useful as plasticizers for cellulose resins and vinyl resins.

[0004] Furthermore, Non-Patent Document 3 discloses that ethyl α-(ethoxycarbonyl)oxyisobutyrate can be synthesized by reacting ethyl α-hydroxyisobutyrate with diethyl carbonate in the presence of a sodium ethoxide catalyst. Furthermore, Non-Patent Document 4 discloses that methyl α-(ethoxycarbonyl)oxyisobutyrate is produced by hydrolysis of the corresponding trimethylsilylcarboimide compound. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Pat. No. 3,368,943 [Non-patent literature]

[0006] [Non-Patent Document 1] "Synthetic Fragrances: Chemistry and Product Knowledge, Revised and Expanded Edition," Chemical Daily, 2016, pp. 580-582 [Non-Patent Document 2] Journal of Organic Chemistry, 1948, Vol.13, p.254-264 [Non-Patent Document 3] Journal of the American Chemical Society, 1959, Vol.81, p.3083-3088 [Non-Patent Document 4] Journal of Organic Chemistry, 1987, vol.52(12), p.2584-2586 Summary of the Invention [Problem to be solved by the invention]

[0007] The problem to be solved by the present invention is to provide an isobutyric acid ester compound having a carbonate group at the α-position, which is useful as a fragrance or blended fragrance material. Another problem to be solved by the present invention is to provide a fragrance composition containing the compound as an active ingredient. [Means for solving the problem]

[0008] The present inventors synthesized various compounds and conducted extensive research into their odors, and found that specific ester compounds of isobutyric acid having a carbonate group at the α-position are useful as fragrances and blended fragrance materials. That is, the present invention is as follows.

[0009] <1> A fragrance composition comprising a compound represented by formula (1) as an active ingredient. [ka] (In formula (1), R 1 R represents a linear, branched or cyclic alkyl group having 1 to 4 carbon atoms. 2 represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms. <2> In formula (1), R 1 is a methyl group or an ethyl group. <1> The fragrance composition according to claim 1. <3> In formula (1), R 2 is an isopropyl group, a secondary butyl group or an isobutyl group, <1> or <2> The fragrance composition according to claim 1. <4> A compound represented by formula (2). [ka] (In formula (2), R 3 R represents a linear, branched or cyclic alkyl group having 1 to 4 carbon atoms. 4 represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms. 3 = ethyl group and R 4 = methyl group, R 3 = ethyl group and R 4 = ethyl group, and 3 = n-butyl group and R 4 =Excluding compounds with an ethyl group.) <5> In formula (2), R 3 is a methyl group or an ethyl group. <4> The compound according to claim 1, <6> In formula (2), R 4 is an isopropyl group, a secondary butyl group or an isobutyl group, <4> or <5> The compound according to claim 1, Effect of the Invention

[0010] According to the present invention, it is possible to provide an isobutyric acid ester compound having a carbonate group at the α-position, which is useful as a fragrance or blended fragrance material, and further, it is possible to provide a fragrance composition containing, as an active ingredient, an isobutyric acid ester compound having a carbonate group at the α-position. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] [Fragrance composition and use] The fragrance composition of the present invention contains a compound represented by the following formula (1) as an active ingredient. Although some isobutyric acid ester compounds having a carbonate group at the α-position have been reported, the inherent scent of isobutyric acid esters having a carbonate group at the α-position has not been described in the prior art.

[0012] The present invention will be described in detail below. <Compound represented by formula (1)> The compound used in the fragrance composition of the present invention (hereinafter also referred to as "isobutyric acid ester having a carbonate group at the α-position") is represented by the following formula (1). [ka] (In formula (1), R 1 R represents a linear, branched or cyclic alkyl group having 1 to 4 carbon atoms. 2 represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms.

[0013] In formula (1), R 1 Specific examples of the alkyl group include a methyl group, an ethyl group, a normal propyl group, an isopropyl group, a normal butyl group, an isobutyl group (2-methylpropyl group), a secondary butyl group (1-methylpropyl group), a tertiary butyl group, a cyclopropyl group, a cyclobutyl group, etc. Preferred are a methyl group, an ethyl group, a normal propyl group, an isopropyl group, a normal butyl group, or an isobutyl group (2-methylpropyl group), and more preferred are a methyl group or an ethyl group.

[0014] In formula (1), R 2 Specific examples of the alkyl groups include methyl, ethyl, normal propyl, isopropyl, normal butyl, isobutyl (2-methylpropyl), secondary butyl (1-methylpropyl), tertiary butyl, normal pentyl, 1-methylbutyl (2-pentyl), 2-methylbutyl, 3-methylbutyl, neopentyl (2,2-dimethylpropyl), 2-methylbutan-2-yl, 1-ethylpropyl (3-pentyl), 3-methylbutan-2-yl, normal hexyl, and 1-methylpentyl. Examples of the aryl group include 2-hexyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 2-methylpentan-2-yl group, 2,2-dimethylbutyl group, 3,3-dimethylbutyl group, 3-methylpentan-2-yl group, 2,3-dimethylbutyl group, 4-methylpentan-2-yl group, 3-hexyl group, 2-ethylbutyl group, 2,3-dimethylbutan-2-yl group, 3,3-dimethylbutan-2-yl group, 4-methylpentan-3-yl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, and cyclohexyl group. Preferred are isopropyl group, secondary butyl group, and isobutyl group.

[0015] R 1 or R 2 When has an asymmetric carbon, the compound represented by formula (1) includes any one of the optical isomers thus produced or a mixture in any ratio.

[0016] The compound represented by the above formula (1) is useful as a fragrance or blended fragrance material, has a floral scent, and in addition, 1 or R 2 Depending on the type, the scent can be fruity, woody, spicy, green, minty, etc. Preferably, R 1 is a methyl group. Preferably, R 1 is an ethyl group. Preferably, R 2 is an isopropyl group. Preferably, R2 is a secondary butyl group. Preferably, R 2 is an isobutyl group. Particularly preferably, R 1 is a methyl group, and R 2 is an isopropyl group. Particularly preferably, R 1 is an ethyl group, and R 2 is an isopropyl group. Particularly preferably, R 1 is a methyl group, and R 2 is a secondary butyl group. Particularly preferably, R 1 is an ethyl group, and R 2 is a secondary butyl group. Particularly preferably, R 1 is a methyl group, and R 2 is an isobutyl group. Particularly preferably, R 1 is an ethyl group, and R 2 is an isobutyl group.

[0017] In the present invention, examples of the compound represented by formula (1) include compounds represented by any of the following formulae (1-1) to (1-34), and particularly preferred compounds are compounds represented by any of the following formulae (1-4), (1-5), (1-8), (1-12), (1-13), and (1-16).

[0018] [ka]

[0019] [ka]

[0020] [ka]

[0021] The compound represented by formula (1) is useful as a fragrance since it has an excellent fragrance by itself as described below. Generally, fragrances are rarely used as single items, but are often used as blended fragrances (fragrance compositions) in which multiple fragrances are blended according to a purpose. The compound represented by formula (1) is useful as a fragrance (also called a "blended fragrance material") to be blended in a blended fragrance (fragrance composition), and the fragrance composition of the present invention contains the compound represented by formula (1) as an active ingredient. As a fragrance, the compound represented by the above formula (1) may be used alone or in combination of two or more kinds. In addition, the compound represented by formula (1) does not exclude the inclusion of small amounts of impurities, by-products, contaminants, etc., within the scope that does not impair the effects of the present invention.

[0022] The compound represented by formula (1) has a floral odor as well as a fruity, woody, spicy, green, minty, etc. odor, and is also excellent in diffusibility. The compound represented by formula (1) may be added alone as a fragrance to various cosmetics, health and hygienic materials, medicines, daily necessities, foods, etc. to impart an odor, or the compound represented by formula (1) may be mixed with other blended fragrance materials, etc. to prepare a fragrance composition (blended fragrance) described below, which is then blended into various products to impart an odor. Among these, from the viewpoint of obtaining a desired odor, it is preferable to blend the compound represented by formula (1) as a blended fragrance material into a fragrance composition to prepare a fragrance composition containing the compound represented by formula (1) as an active ingredient, and blend the fragrance composition into a product to impart an odor.

[0023] <Fragrance composition> The fragrance composition (blended fragrance) of the present invention contains a compound represented by formula (1) as an active ingredient. There are no particular limitations on the composition as long as it contains at least one type of compound represented by formula (1), and it may contain two or more types of compounds represented by formula (1). The fragrance composition of the present invention may contain the compound represented by formula (1) as an active ingredient, and other ingredients are not particularly limited, but it is preferable that the fragrance composition further contains other blended fragrance materials (hereinafter also referred to as "conventional fragrances"). It should be noted that a "fragrance composition (blended fragrance)" is a composition that imparts a fragrance when added to various cosmetics, pharmaceuticals, foods, beverages, etc., or a composition that can be used as such in perfumes, etc., and may contain additives such as solvents as necessary in addition to conventional fragrances. The amount of the compound represented by formula (1) to be blended varies depending on the type of compound, the type and intensity of the desired fragrance, etc., but the amount of the compound represented by formula (1) in the fragrance composition is preferably 0.001 mass% or more, more preferably 0.01 mass% or more, even more preferably 0.1 mass% or more, and is preferably 90 mass% or less, more preferably 70 mass% or less, even more preferably 50 mass% or less.

[0024] The conventional fragrance is not particularly limited as long as it is a conventionally known fragrance component, and a wide range of fragrances can be used. For example, the following can be selected and used alone or in any mixture of two or more kinds in any ratio: For example, hydrocarbons such as limonene, α-pinene, β-pinene, terpinene, cedrene, longifolene, and valencene; linalool, citronellol, geraniol, nerol, terpineol, dihydromyrcenol, ethyl linalool, farnesol, nerolidol, cis-3-hexenol, cedrol, menthol, borneol, β-phenylethyl alcohol, benzyl alcohol, phenylhexanol, 2,2,6-trimethylcyclohexyl-3-hexanol, 1-(2-t-butylcyclohexyloxy)-2-butanol, 4- Alcohols such as isopropylcyclohexanemethanol, 4-t-butylcyclohexanol, 4-methyl-2-(2-methylpropyl)tetrahydro-2H-pyran-4-ol, 2-methyl-4-(2,2,3-trimethyl-3-cyclopenten-1-yl)-2-buten-1-ol, 2-ethyl-4-(2,2,3-trimethyl-3-cyclopenten-1-yl)-2-buten-1-ol, isocamphylcyclohexanol, and 3,7-dimethyl-7-methoxyoctan-2-ol; phenols such as eugenol, thymol, and vanillin;Linalyl formate, citronellyl formate, geranyl formate, n-hexyl acetate, cis-3-hexenyl acetate, linalyl acetate, citronellyl acetate, geranyl acetate, neryl acetate, terpinyl acetate, nopyr acetate, bornyl acetate, isobornyl acetate, ot-butylcyclohexyl acetate, pt-butylcyclohexyl acetate, tricyclodecenyl acetate, benzyl acetate, styraryl acetate, cinnamyl acetate, dimethyl benzyl acetate, Dimethylbenzylcarbinyl acetate, 3-pentyltetrahydropyran-4-yl acetate, citronellyl propionate, tricyclodecenyl propionate, allyl cyclohexyl propionate, ethyl 2-cyclohexyl propionate, benzyl propionate, citronellyl butyrate, dimethylbenzylcarbinyl n-butyrate, tricyclodecenyl isobutyrate, methyl 2-nonenoate, methyl benzoate, benzyl benzoate, methyl cinnamate, methyl salicylate, n-hexyl salicylate esters such as cis-3-hexenyl salicylate, geranyl tiglate, cis-3-hexenyl tiglate, methyl jasmonate, methyl dihydrojasmonate, methyl 2,4-dihydroxy-3,6-dimethylbenzoate, ethyl methylphenylglycidate, methyl anthranilate, and flutate; n-octanal, n-decanal, n-dodecanal, 2-methylundecanal, 10-undecenal, citronellal, citral, hydroxycitronellal, dimethyltetrahydrobenzaldehyde, and the like. aldehydes such as cinnamic aldehyde, 4(3)-(4-hydroxy-4-methylpentyl)-3-cyclohexene-1-carbaldehyde, 2-cyclohexylpropanal, p-butyl-α-methylhydrocinnamic aldehyde, p-isopropyl-α-methylhydrocinnamic aldehyde, p-ethyl-α,α-dimethylhydrocinnamic aldehyde, α-amylcinnamic aldehyde, α-hexylcinnamic aldehyde, piperonal, and α-methyl-3,4-methylenedioxyhydrocinnamic aldehyde;Methylheptenone, 4-methylene-3,5,6,6-tetramethyl-2-heptanone, amylcyclopentanone, 3-methyl-2-(cis-2-penten-1-yl)-2-cyclopenten-1-one, methylcyclopentenolone, rose ketone, gamma-methylionone, alpha-ionone, carvone, menthone, camphor, nootkatone, benzylacetone, anisylacetone, methyl beta-naphthyl ketone, 2,5-dimethyl-4-hydroxy-3(2H)-furanone Ketones such as maltol, 7-acetyl-1,2,3,4,5,6,7,8-octahydro-1,1,6,7-tetramethylnaphthalene, muscone, civetone, cyclopentadecanone, and cyclohexadecenone; acetals and ketals such as acetaldehyde ethyl phenylpropyl acetal, citral diethyl acetal, phenylacetaldehyde glycerin acetal, and ethyl acetoacetate ethylene glycol ketals; anethole, β-naphthalene, Ethers such as butyl methyl ether, β-naphthyl ethyl ether, limonene oxide, rose oxide, 1,8-cineole, racemic or optically active dodecahydro-3a,6,6,9a-tetramethylnaphtho[2,1-b]furan; nitriles such as citronellyl nitrile; γ-nonalactone, γ-undecalactone, σ-decalactone, γ-jasmolactone, coumarin, cyclopentadecanolide, cyclohexadecanolide, ambrette, ethyl lactones such as ambrosialate and 11-oxahexadecanolide; natural essential oils and extracts such as orange, lemon, bergamot, mandarin, peppermint, spearmint, lavender, chamomile, rosemary, eucalyptus, sage, basil, rose, geranium, jasmine, ylang-ylang, anise, clove, ginger, nutmeg, cardamom, cedar, cypress, sandalwood, vetiver, patchouli, labdanum, and other fragrance substances such as synthetic fragrances;

[0025] The fragrance composition may also contain, as components other than the blended fragrance materials, surfactants such as polyoxyethylene lauryl sulfate ether; solvents such as dipropylene glycol, diethyl phthalate, ethylene glycol, propylene glycol, methyl myristate, and triethyl citrate; antioxidants; colorants, etc.

[0026] The compound represented by formula (1) has a floral odor as well as a fruity, woody, spicy, green, minty, or other odor. When combined with a conventional fragrance, the compound can impart a natural fruity, woody, spicy, green, or minty odor as well as a floral odor. Therefore, the compound is useful for imparting an odor to various cosmetics, health and hygienic materials, medicines, daily necessities, foods, and the like.

[0027] Examples of products to which a fragrance composition containing a compound represented by formula (1) can be added in order to impart a fragrance and improve the fragrance of a compound to be blended include various products such as cosmetics, health and hygiene materials, miscellaneous goods, beverages, foods, quasi-drugs, and pharmaceuticals, and examples of such products include fragrance products such as perfumes and colognes; shampoos, rinses, hair tonics, hair creams, mousses, gels, pomades, sprays, and other hair cosmetics; lotions, beauty serums, creams, milky lotions, packs, foundations, It can be used as a fragrance component in skin cosmetics such as face powder, lipstick, and various types of make-up; dishwashing detergents, laundry detergents, softeners, disinfectant detergents, deodorizing detergents, room fresheners, furniture care, glass cleaners, furniture cleaners, floor cleaners, disinfectants, insecticides, bleaches, germicides, repellents, and other various health and hygiene detergents; toothpaste, mouthwash, bath additives, antiperspirant products, perm solution, and other quasi-drugs; miscellaneous goods such as toilet paper and tissue paper; pharmaceuticals, etc.; and foods, etc.

[0028] The blending amount of the fragrance composition in the above-mentioned product is not particularly limited, and can be selected from a wide range depending on the type, properties, and sensory effect of the product to be scented, etc. For example, it is 0.00001% by mass or more, preferably 0.0001% by mass or more, and more preferably 0.001% by mass or more, and in the case of fragrances such as perfume, it may be 100% by mass, but is preferably 80% by mass or less, more preferably 60% by mass or less, and even more preferably 40% by mass or less.

[0029] [Compound represented by formula (2)] The compound of the present invention is represented by formula (2). Hereinafter, the compound represented by formula (2) is also referred to as "the isobutyric acid ester of the present invention." [ka] (In formula (2), R 3 R represents a linear, branched or cyclic alkyl group having 1 to 4 carbon atoms. 4 represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms. 3 = ethyl group and R 4 = methyl group, R 3 = ethyl group and R 4 = ethyl group, and 3 = n-butyl group and R 4 =Excluding compounds with an ethyl group.)

[0030] In formula (2), R 3 Specific examples of the alkyl group include a methyl group, an ethyl group, a normal propyl group, an isopropyl group, a normal butyl group, an isobutyl group (2-methylpropyl group), a secondary butyl group (1-methylpropyl group), a tertiary butyl group, a cyclopropyl group, a cyclobutyl group, etc. Preferred are a methyl group, an ethyl group, a normal propyl group, an isopropyl group, a normal butyl group, or an isobutyl group (2-methylpropyl group), and more preferred are a methyl group or an ethyl group.

[0031] In formula (2), R 4Specific examples of the alkyl groups include methyl, ethyl, normal propyl, isopropyl, normal butyl, isobutyl (2-methylpropyl), secondary butyl (1-methylpropyl), tertiary butyl, normal pentyl, 1-methylbutyl (2-pentyl), 2-methylbutyl, 3-methylbutyl, neopentyl (2,2-dimethylpropyl), 2-methylbutan-2-yl, 1-ethylpropyl (3-pentyl), 3-methylbutan-2-yl, normal hexyl, and 1-methylpentyl. Examples of the aryl group include 2-hexyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 2-methylpentan-2-yl group, 2,2-dimethylbutyl group, 3,3-dimethylbutyl group, 3-methylpentan-2-yl group, 2,3-dimethylbutyl group, 4-methylpentan-2-yl group, 3-hexyl group, 2-ethylbutyl group, 2,3-dimethylbutan-2-yl group, 3,3-dimethylbutan-2-yl group, 4-methylpentan-3-yl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, and cyclohexyl group. Preferred are isopropyl group, secondary butyl group, and isobutyl group.

[0032] In the formula (2), R 3 = ethyl group and R 4 = methyl group, R 3 = ethyl group and R 4 = ethyl group, and 3 = n-butyl group and R 4 =Excluding compounds with an ethyl group.

[0033] R 3 or R 4 When has an asymmetric carbon, the compound represented by formula (2) includes any one of the optical isomers thus produced or a mixture in any ratio.

[0034] The isobutyric acid ester of the present invention is represented by the formula (2), 3 is preferably a methyl group or an ethyl group. 4is preferably an isopropyl group, a secondary butyl group, or an isobutyl group, provided that R 3 = ethyl group and R 4 = methyl group, R 3 = ethyl group and R 4 = ethyl group, and 3 = n-butyl group and R 4 =Excluding compounds with an ethyl group. That is, the isobutyric acid ester of the present invention is particularly preferably the following compound. Preferably, R 3 is a methyl group. Preferably, R 3 is an ethyl group. 4 Excluding those in which is a methyl group or an ethyl group. Preferably, R 4 is an isopropyl group. Preferably, R 4 is a secondary butyl group. Preferably, R 4 is an isobutyl group. Particularly preferably, R 3 is a methyl group, and R 4 is an isopropyl group. Particularly preferably, R 3 is an ethyl group, and R 4 is an isopropyl group. Particularly preferably, R 3 is a methyl group, and R 4 is a secondary butyl group. Particularly preferably, R 3 is an ethyl group, and R 4 is a secondary butyl group. Particularly preferably, R 3 is a methyl group, and R 4 is an isobutyl group. Particularly preferably, R 3 is an ethyl group, and R 4 is an isobutyl group.

[0035] The isobutyric acid ester of the present invention is preferably a compound represented by any one of the following formulas (2-1) to (2-26), and particularly preferably a compound represented by any one of the following formulas (2-4), (2-5), (2-8), (2-10), (2-11), or (2-14).

[0036] [ka]

[0037] [ka]

[0038] The isobutyric acid ester of the present invention can be prepared by converting the compound represented by formula (2) into an isobutyric acid ester represented by formula (2) 3 = Ethyl group R 4 = methyl group, R 3 = Ethyl group R 4 = ethyl group, and 3 = normal butyl group, R 4 = ethyl group is excluded. Therefore, the isobutyric acid ester of the present invention is useful as a fragrance alone, and is also useful as an active ingredient of a fragrance composition.

[0039] [Method for producing the isobutyric acid ester and the compound represented by formula (1) of the present invention] The method for producing the isobutyric acid ester of the present invention represented by formula (2) and the compound represented by formula (1) is not particularly limited, and may be appropriately selected from conventionally known methods.

[0040] For example, an isobutyric acid ester having a carbonate group at the α-position can be produced by reacting an α-hydroxyisobutyric acid ester or an alkali metal alkoxide thereof with a halogenoformic acid ester. The reaction formula for this reaction is shown in the following formula (3). [ka] In formula (3), R 1R represents a linear, branched or cyclic alkyl group having 1 to 4 carbon atoms. 2 represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms; M represents a hydrogen atom or an alkali metal atom such as sodium, potassium or cesium; and X represents a halogen atom such as chlorine, bromine or iodine.

[0041] In addition, an isobutyric acid ester having a carbonate group at the α-position can be produced by transesterification of an α-hydroxyisobutyric acid ester with a carbonate ester in the presence of a catalyst. The reaction formula for this reaction is shown in the following formula (4). [ka] In formula (4), R 1 R represents a linear, branched or cyclic alkyl group having 1 to 4 carbon atoms. 2 represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms.

[0042] In addition, the desired isobutyric acid ester having a carbonate group at the α-position can be produced by transesterification of another isobutyric acid ester having a carbonate group at the α-position with an alcohol in the presence of a catalyst. The reaction formula for this reaction is shown in the following formula (5). [ka] In formula (5), R 1 R represents a linear, branched or cyclic alkyl group having 1 to 4 carbon atoms. 2 represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms; R 11 is R 1 A group different from R 12 is R 2 represents a group different from that.

[0043] For the catalysts, reaction methods, reaction conditions, reaction apparatuses, etc. used in these reactions, conventionally known catalysts, reaction methods, reaction conditions, and reaction apparatuses can be used, and there are no particular limitations. Also, for the method of purifying the isobutyric acid ester of the present invention represented by the obtained formula (2) and the compound represented by formula (1), a conventionally known purification method can be adopted, and there are no limitations whatsoever.

Examples

[0044] Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[0045] The evaluation of the reaction results was carried out according to the following formula. Reaction yield (%) = [(number of moles of the produced ester in the reaction solution) / (number of moles of the raw material ester in the charged solution)] × 100%

[0046] <Gas chromatography analysis (GC analysis)> Apparatus: "GC-2010" (manufactured by Shimadzu Corporation, product name) Detector: FID Column: "DB-1" (J&W capillary column, product name) (0.25 mmφ × 60 m × 0.25 μm)

[0047] <NMR spectrum analysis> The identification of the ester was 1 performed by 13 1H-NMR measurement and 13C-NMR measurement. The measurement conditions are shown below. 〔 1 1H-NMR〕 Nuclide: 1 1H Measurement frequency: 500 MHz Measurement sample: 5% CDCl3 solution 〔 13 13C-NMR〕 Nuclide: 13 13C Measurement frequency: 125 MHz Measurement sample: 5% CDCl3 solution

[0048] <Gas Chromatography-Mass Spectrometry (GC-MS Analysis)> The compounds were identified by determining their molecular weights using GC-MS (chemical ionization method [CI+], high-resolution mass spectrometry [millimass]). The measurement conditions are shown below. GC device: "Agilent 7890A" (product name, manufactured by Agilent) GC measurement conditions Column: "DB-1" (J&W capillary column, product name) (0.25 mmφ x 30 m x 0.25 μm) MS device: "JMS-T100GCV" (product name, manufactured by JEOL Ltd.) MS measurement conditions, chemical ionization method Detector conditions: 200 eV, 300 μA Reagent gas: Isobutane The exact mass values ​​of the fragments detected in a protonated state by chemical ionization and the chemical formulas assigned thereto are shown.

[0049] <Product isolation by chromatographic method> The following materials were used for chromatographic product isolation: Filler: "Wakogel C-200" (product name, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Developing solvent: ethyl acetate-hexane

[0050] <Reference Example 1: Synthesis of isopropyl α-hydroxyisobutyrate> A 300 mL glass flask equipped with a distillation tube was charged with 88.7 g of methyl α-hydroxyisobutyrate (manufactured by Mitsubishi Gas Chemical Co., Ltd.), 106.1 g of isopropanol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and 0.21 g of sodium methoxide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). The transesterification reaction was carried out while heating and refluxing under normal pressure, and the reaction was carried out for 48 hours while the produced methanol was removed from the system. As a result, isopropyl α-hydroxyisobutyrate was obtained with a reaction yield of 98.4% by the reaction of the following formula (6). Water was added to the reaction system to deactivate the catalyst, and then reduced pressure distillation was carried out to obtain 77.7 g of isopropyl α-hydroxyisobutyrate (purity by GC analysis (hereinafter also referred to as GC purity): 99.6%) as the fraction at 40 mmHg and 65°C. [ka]

[0051] <Reference Examples 2-3: Synthesis of various α-hydroxyisobutyric acid esters> Using the same reaction apparatus as in Reference Example 1, an appropriate amount of methyl α-hydroxyisobutyrate (manufactured by Mitsubishi Gas Chemical Co., Inc.) and various alcohols (isobutanol, secondary butanol) were subjected to an ester exchange reaction under appropriate reaction conditions while heating in the presence of an appropriate catalyst such as titanium tetraalkoxide and / or sodium alkoxide, and in some cases in the presence of a solvent such as hexane or toluene. The ester exchange reaction was completed while the methanol produced by the reaction was removed from the system by distillation or azeotropy with the reaction solvent under reaction conditions, and the following α-hydroxyisobutyric acid esters were obtained by carrying out the same separation operation as in Reference Example 1. The GC purity of the obtained isobutyric acid esters is also shown. Isobutyl α-hydroxyisobutyrate (GC purity: 99.6%) Secondary butyl α-hydroxyisobutyrate (GC purity: 99.6%)

[0052] Example 1: Synthesis of isopropyl α-(methoxycarbonyl)oxyisobutyrate A 50mL glass flask equipped with a stirring device and a dropping device was filled with 5.0g of isopropyl α-hydroxyisobutyrate synthesized in Reference Example 1, 5.6g of N-methylimidazole (Tokyo Chemical Industry Co., Ltd.), and 6.5mL of dichloromethane (Fujifilm Wako Pure Chemical Industries, Ltd.), and cooled to 0°C. While stirring, a solution of 4.9g of methyl chloroformate (Tokyo Chemical Industry Co., Ltd.) dissolved in 6.5mL of dichloromethane (Fujifilm Wako Pure Chemical Industries, Ltd.) was slowly dropped. After the dropwise addition, stirring was continued for 2 hours while maintaining 0°C. Thereafter, cooling was stopped, and stirring was continued while slowly returning to room temperature, and the reaction was continued for 15 hours. GC analysis of the reaction solution confirmed that isopropyl α-(methoxycarbonyl)oxyisobutyrate was obtained in a reaction yield of 81% by the reaction of the following formula (6). The mixture was then washed twice with 10% aqueous sodium bicarbonate and twice with saturated aqueous ammonium chloride, dried over sodium sulfate, concentrated, and subjected to column chromatography to obtain 3.2 g of isopropyl α-(methoxycarbonyl)oxyisobutyrate (GC purity: 99.6%). The results of NMR spectrum analysis and GC-MS analysis of the product are shown below.

[0053] [α-(Methoxycarbonyl)oxyisobutyric acid isopropyl] 1 H NMR (500 MHz, CDCl3) δ1.251 (6H, d, J = 6.0Hz), 1.590 (6H, s), 3.768 (3H, s), 5.070 (1H, sept(7), J = 6.25Hz) 13 C NMR (125 MHz, CDCl3) δ21.66, 24.55, 54.77, 69.11, 80.42, 154.26, 171.75 Exact.Mass 205.10847 (C9H 16 O5, parent peak), 129.09197 (C7H 12 O2)

[0054] [ka]

[0055] <Examples 2 to 6: Synthesis of various isopropyl α-(alkoxycarbonyl)oxyisobutyrates> Using the same reaction apparatus as in Example 1, the reaction was carried out using appropriate amounts of isopropyl α-hydroxyisobutyrate prepared in Reference Example 1, various chloroformate esters (ethyl chloroformate, normal propyl chloroformate, isopropyl chloroformate, normal butyl chloroformate, isobutyl chloroformate; all manufactured by Tokyo Chemical Industry Co., Ltd.), N-methylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.), and dichloromethane (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). The following various isopropyl α-(alkoxycarbonyl)oxyisobutyrates were obtained by column chromatography in the same manner as in Example 1. The GC purity, NMR spectrum analysis, and GC-MS analysis results of the obtained esters are also shown.

[0056] [α-(Ethoxycarbonyl)oxyisobutyric acid isopropyl] GC purity: 99.7% 1 H NMR (500 MHz, CDCl3) δ1.251 (6H, d, J = 6.5Hz), 1.315 (3H, t, J = 7.5Hz), 1.591 (6H, s), 4.179 (2H, q, J = 7.0Hz), 5.070 (1H, spt(7), J = 6.25Hz) 13 C NMR (125 MHz, CDCl3) δ14.34, 21.67, 24.57, 64.06, 69.04, 80.21, 153.64, 171.83 Exact.Mass 219.12564 (C 10 H 18 O5, parent peak)

[0057] [α-(normal propoxycarbonyl)oxyisobutyric acid isopropyl] GC purity: 99.9% 1H NMR (500 MHz, CDCl3) δ0.97 (3H, t, J = 7.5 Hz), 1.25 (6H, d, J = 6.5 Hz), 1.59 (6H, s), 1.70 (2H, qt, J = 6.5, 7.5 Hz), 4.08 (2H, t, J = 6.5 Hz), 5.07 (1H, sept, J = 6.5 Hz) 13 C NMR (125 MHz, CDCl3) δ10.12, 21.51, 21.96, 24.43, 68.87, 69.51, 80.04, 153.65, 171.67 Exact.Mass 233.13737 (C 11 H 20 O5, parent peak)

[0058] [α-(isopropoxycarbonyl)oxyisobutyric acid isopropyl] GC purity: 99.3% 1 H NMR (500 MHz, CDCl3) δ1.249 (6H, d, J = 6.5Hz), 1.305 (6H, d, J = 6.5Hz), 1.587 (6H, s), 4.844 (1H, sept(7), J = 6.25Hz), 5.068 (1H, sept(7), J = 6.25Hz) 13 C NMR (125 MHz, CDCl3) δ21.69, 21.85, 24.60, 69.00, 72.12, 80.07, 153.16, 171.92 Exact.Mass 233.13768 (C 11 H 20 O5, parent peak), 129.09123 (C7H 12 O2)

[0059] [α-(n-butoxycarbonyl)oxyisobutyric acid isopropyl] GC purity: 99.8% 11H NMR (500 MHz, CDCl3) δ0.94 (3H, t, J = 7.5 Hz), 1.25 (6H, d, J = 6.5 Hz), 1.36 - 1.46 (2H, m), 1.59 (6H, s), 1.62 - 1.69 (2H, m), 4.12 (2H, t, J = 6.5 Hz), 5.07 (1H, sept, J = 6.5 Hz) 13 13C NMR (125 MHz, CDCl3) δ13.60, 18.85, 21.52, 24.43, 30.62, 67.81, 68.87, 80.04, 153.65, 171.70 Exact.Mass 247.15379 (C 12 H 22 O5, parent peak)

[0060] [Isopropyl α-(isobutoxycarbonyl)oxyisobutyrate] GC purity: 99.5% 1 1H NMR (500 MHz, CDCl3) δ0.95 (6H, d, J = 7.0Hz), 1.24 (6H, d, J = 6.5Hz), 1.59 (6H, s), 1.94 - 2.03 (1H, m), 3.90 (2H, d, J = 6.5Hz), 5.06 (1H, sept, J = 6.5Hz) 13 13C NMR (125 MHz, CDCl3) δ18.85, 21.51, 24.43, 27.74, 68.87, 73.98, 80.03, 153.73, 171.72 Exact.Mass 247.15746 (C 12 H 22 O5, parent peak)

[0061] [Example 7: Synthesis of Isobutyl α-(ethoxycarbonyl)oxyisobutyrate] Using the same reaction apparatus as in Example 1, the reaction was carried out using appropriate amounts of isobutyl α-hydroxyisobutyrate prepared in Reference Example 2, ethyl chloroformate (Tokyo Chemical Industry Co., Ltd.), N-methylimidazole (Tokyo Chemical Industry Co., Ltd.), and dichloromethane (Fujifilm Wako Pure Chemical Industries, Ltd.). The reaction was carried out in the same manner as in Example 1, and the following isobutyl α-(ethoxycarbonyl)oxyisobutyrate was obtained by column chromatography. The GC purity, NMR spectrum analysis, and GC-MS analysis results of the obtained ester are also shown.

[0062] [α-(Ethoxycarbonyl)oxyisobutyric acid isobutyl] GC purity: 99.5% 1 H NMR (500 MHz, CDCl3) δ0.94 (6H, d, J = 7.0Hz), 1.31 (3H, t, J =7.0Hz), 1.61 (6H, s), 1.96 (1H, nonatet, J = 7.0Hz), 3.93 (2H, d, J = 7.0Hz), 4.17 (1H, q, J = 7.0Hz), 4.18 (1H, q, J = 7.0Hz) 13 C NMR (125 MHz, CDCl3) δ14.16, 18.92, 24.57, 27.62, 63.98, 71.47, 80.14, 153.54, 172.27 Exact.Mass 233.13845 (C 11 H 20 O5, parent peak), 143.10793 (C8H 14 O2)

[0063] <Example 8: Synthesis of secondary butyl α-(ethoxycarbonyl)oxyisobutyrate> Using the same reaction apparatus as in Example 1, the reaction was carried out using appropriate amounts of secondary butyl α-hydroxyisobutyrate prepared in Reference Example 3, ethyl chloroformate (Tokyo Chemical Industry Co., Ltd.), N-methylimidazole (Tokyo Chemical Industry Co., Ltd.), and dichloromethane (Fujifilm Wako Pure Chemical Industries, Ltd.). The same procedure as in Example 1 was carried out to obtain the following secondary butyl α-(ethoxycarbonyl)oxyisobutyrate by column chromatography. The GC purity, NMR spectrum analysis, and GC-MS analysis results of the obtained ester are also shown.

[0064] [Secondary butyl α-(ethoxycarbonyl)oxyisobutyrate] GC purity: 99.8% 1 H NMR (500 MHz, CDCl3) δ0.90 (3H, t, J = 7.5Hz), 1.22 (3H, d J = 6.0Hz), 1.31 (3H, t, J = 7.0Hz), 1.56-1.65 (2H, m), 1.60 (6H, s), 4.18 (1H, q, J = 7.0Hz), 4.18 (1H, q, J = 7.0Hz), 4.90 (1H, sext, J = 6.5Hz). 13 C NMR (125 MHz, CDCl3) δ9.49, 14.16, 19.09, 24.42, 24.51, 28.59, 63.89, 73.44, 80.11, 153.45, 171.78 Exact.Mass 233.14004 (C 11 H 20 O5, parent peak), 177.07780 (C7H 12 O5)

[0065] The various isobutyric acid esters having a carbonate group at the α-position obtained by the above method were subjected to an odor evaluation by a perfumer, and the results are shown in Table 1.

[0066] [Table 1]

[0067] Example 9: Fragrance composition for fruity floral shower gel A fragrance composition was prepared by adding 75 parts by mass of the isopropyl α-(ethoxycarbonyl)oxyisobutyrate obtained in Example 2 to 925 parts by mass of a fragrance composition having the composition shown in Table 2. According to an odor evaluation by a perfumer, the addition of isopropyl α-(ethoxycarbonyl)oxyisobutyrate of Example 2 to the fragrance composition having the composition shown in Table 2 increased the intensity of the fragrance and enhanced the diffusibility, resulting in a more expansive and cohesive fragrance with a more refreshing fruity floral feel. As a result, a novel fragrance composition for fruity floral shower gel was obtained.

[0068] [Table 2] [Industrial Applicability]

[0069] The isobutyric acid ester compound of the present invention having a carbonate group at the α-position has an excellent odor and is expected to be used as a fragrance by itself. In addition, by using the compound as a blended fragrance ingredient, a fragrance composition having an excellent odor can be obtained, and by blending the compound in various products, the desired fragrance-imparting properties can be exhibited.

Claims

1. A fragrance composition comprising a compound represented by formula (1) as an active ingredient. 【Chemistry 1】 (In formula (1), R 1 represents a linear, branched or cyclic alkyl group having 1 to 4 carbon atoms; R 2 represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms.

2. In formula (1), R 1 The fragrance composition according to claim 1 , wherein is a methyl group or an ethyl group.

3. In formula (1), R 2 The fragrance composition according to claim 1 or 2, wherein is an isopropyl group, a secondary butyl group or an isobutyl group.

4. A compound represented by formula (2). 【Chemistry 2】 (In formula (2), R 3 represents a linear, branched or cyclic alkyl group having 1 to 4 carbon atoms; R 4 represents a linear, branched or cyclic alkyl group having 1 to 6 carbon atoms. 3 = ethyl group and R 4 = methyl group, R 3 = ethyl group and R 4 = an ethyl group, and 3 = normal butyl group and R 4 = Excluding compounds with an ethyl group.)

5. In formula (2), R 3 The compound according to claim 4 , wherein is a methyl group or an ethyl group.

6. In formula (2), R 4 6. The compound according to claim 4 or 5, wherein is an isopropyl group, a secondary butyl group or an isobutyl group.

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