WO2020121905A1 - Diester compound as fragrance precursor - Google Patents

Abstract

[Problem] To provide a novel diester compound that can be used as a fragrance precursor. [Solution] Provided are: a diester compound that can be used as a fragrance precursor, the diester compound having cyclohexanol or a derivative thereof, an aroma compound having a hydroxyl group, and a diester bond linking the two in the molecule; a fragrance composition containing the diester compound; and a consumer product containing the diester compound or the fragrance composition. Also provided is a method for imparting or enhancing the residual scent of a consumer product, the method including blending the diester compound or the fragrance composition with a consumer product.

Description

Diester compounds as fragrance precursors

The present invention relates to a diester compound, and more particularly to a cyclohexanol or a derivative thereof, an aroma compound having a hydroxyl group, and a diester compound having a diester bond connecting these two in the molecule and usable as a perfume precursor. .

Recently, consumers' demands for foods and drinks and cosmetics have become more sophisticated and diversified, but attention has been paid to fragrances, and the characteristics of fragrances are an important factor for the appeal of products. For example, in the field of perfumery and cosmetics, many techniques have been proposed for increasing the residual aroma of various laundry detergents, and among them, so-called perfume precursors having a molecular structure capable of releasing an aroma compound by light, heat, physical contact, etc. Research on the body is being actively conducted.

For example, various flavor precursors containing an ester bond in the molecule have been proposed.

In Patent Document 1, as a fragrance precursor composition which, when applied to the skin, can continuously obtain a scent of sufficient strength from the skin, contains the components (A) to (C) and conditions 1 to 3 A fragrance precursor composition satisfying the above conditions, wherein components (A) to (C) are (A): an unsaturated alcohol fragrance having 6 to 10 carbon atoms and a saturated monocarboxylic acid having 12 to 18 carbon atoms, or 1 or 2 or more perfume precursors selected from esters with saturated dicarboxylic acids having 4 to 10 carbon atoms, (B): one or more polyoxyethylene sorbitan fatty acid esters having HLB of 8 to 15 , (C): one or more selected from a fatty acid having 16 to 22 carbon atoms and a monoglyceride of the fatty acid, the conditions 1 to 3 and the condition 1: the mass ratio (B)/(A) is 0.0001 or more and 0.8 or less, condition 2: mass ratio (C)/(A) is 0.02 or more and 4 or less, condition 3: mass ratio [(B)+(C)]/(A) is 0. A composition of 55 or more and 2 or less is disclosed, and in the Examples, (A) is a diester of an unsaturated alcohol flavor having 6 or more and 10 or less carbon atoms and a dicarboxylic acid, and 2 molecules of the unsaturated alcohol. It is said to be a diester of dicarboxylic acid with dicarboxylic acid, that is, a diester compound having a bilaterally symmetrical structure, and exerts a sustained release effect when the unsaturated alcohol flavor is digeranyl or the like.

Patent Document 2 proposes a fragrance precursor composed of an ester of a fragrance having a phenol structure or a hydroxy-4-pyrone structure and an aliphatic dicarboxylic acid having 6 to 20 carbon atoms, and ethyl vanillin in Examples. It is said to have excellent sustained release effects.

Patent Document 3 proposes a fragrance precursor comprising an ester of a fragrance having a phenol structure or a hydroxy-4-pyrone structure and an aliphatic monocarboxylic acid having 8 or more and 18 or less carbon atoms, such as ethyl vanillin and vanillin. , Ethyl maltol, maltol and raspberry ketone are said to have high sustained release effects.

Regarding other precursors having an ester structure, Patent Document 4 discloses that by using a compound having a serine-prolyl ester bond and a structure similar thereto, an N-accompanied by amide bond cleavage in a neutral aqueous solution. The to-O acyl group transfer reaction proceeds (diketopiperazine is formed), and the resulting ester moiety is hydrolyzed to release the functional molecule, and such a reaction occurs continuously (cascade). Thus, a sustained-release carrier material having a molecular design has been proposed.

Further, as a fragrance precursor having a silicate ester structure, Patent Document 5 proposes a silicate ester represented by the formula (R ¹ O) ₄ Si or (RO) ₃ SiOSi(RO) ₃ , and ROH and It is described that geraniol has a sustained release effect as a perfume alcohol represented by R ¹ OH, and Patent Document 6 discloses a silicate ester that slowly releases raspberry ketone (also described as 4-(3-oxobutyl)phenol). Have been described.

Furthermore, glycosides of aroma compounds (slow release by decomposition on the human body surface, Patent Document 7), carbonic acid esters (aroma generation upon contact with skin, Patent Document 8), β-ketoesters (Patent Document 9), etc. Proposed.

However, conventional perfume precursors are not always satisfactory in terms of high residual aroma and quality of aroma expressed, and development of new and superior perfume precursors is awaited.

Japanese Patent Laid-Open No. 2018-70806 JP, 2016-117655, A JP, 2005-134754, A JP, 2005-168669, A JP, 2014-141420, A JP, 2013-47325, A Japanese Patent Laid-Open No. 2000-96078 Japanese Patent Laid-Open No. 10-95752 Tokuyo 2000-502746

An object of the present invention is to provide a novel diester compound that can be used as a perfume precursor.

The inventors of the present invention have eagerly searched for an excellent fragrance precursor, and found that a diester compound obtained by connecting a cyclohexanol or a derivative thereof and an aroma compound having a hydroxyl group by a diester bond with an aliphatic dicarboxylic acid has an excellent residual aroma. And found that it is useful as a perfume precursor.

Thus, the present invention provides the following:
[1] A diester compound represented by the following formula A.

[In the formula A, R represents a residue obtained by removing a hydroxyl group from an aroma compound represented by R-OH, n represents an integer of 2 to 11, and R ₂ and R ₃ each independently represent hydrogen or the number of carbon atoms. It represents a linear or branched alkyl group of 1 to 4. (However, the case where n is 2 to 11 and the compounds represented by R—OH and R ₁ —OH are both l-menthol.)]
[2] The diester compound according to [1], wherein the compound represented by R ₁ —OH is menthol or cyclohexanol.
[3] The diester compound according to [1] or [2], wherein the aroma compound represented by R-OH has 4 to 12 carbon atoms.
[4] The diester compound according to any one of [1] to [3], wherein in the fragrance compound represented by R-OH, the OH is a phenolic hydroxyl group.
[5] A fragrance composition containing the diester compound according to any one of [1] to [4].
[6] A consumer product containing the diester compound according to any one of [1] to [4] or the fragrance composition according to [5].
[7] A method for imparting or enhancing the residual aroma of consumer goods, which comprises blending the diester compound according to any one of [1] to [4] or the fragrance composition according to [5] with the consumer goods.

The present invention has made it possible to provide a novel diester compound that can be used as a perfume precursor.

FIG. 1 is a diagram showing the residual aroma of the diester compound of the present invention (or the fragrance precursor of the present invention). FIG. 2 is a diagram showing the residual aroma of the diester compound of the present invention (or the fragrance precursor of the present invention).

(The fragrance precursor of the present invention)
The diester compound of the present invention is a compound represented by the following formula A and can be used as a perfume precursor.

[In the formula A, R represents a residue obtained by removing a hydroxyl group from an aroma compound represented by R-OH, n represents an integer of 2 to 11, and R ₁ represents cyclohexanol represented by R ₁ -OH or It represents a residue obtained by removing a hydroxyl group from its derivative, and R ₂ and R ₃ each independently represent hydrogen or a linear or branched alkyl group having 1 to 4 carbon atoms. (However, the case where n is 2 to 11 and the cyclohexanol represented by R—OH or R ₁ —OH or a derivative thereof is l-menthol is excluded.)]
Hereinafter, in the present specification, the diester compound of the present invention is also referred to as a perfume precursor of the present invention. The perfume precursor means a compound containing an aroma compound moiety in the molecule and capable of releasing the aroma compound as a simple substance.

Although the principle is not clear, in the molecule of the diester compound of the present invention, the portion linked to the aroma compound by a diester bond has a cyclohexane structure, that is, by using cyclohexanol or a derivative thereof, a conventional precursor It is possible that the residual aroma was remarkably improved as compared with. The cyclohexane structure improves hydrophobicity, the interaction with the base material to which the precursor such as a fibrous product is attached becomes stronger, the possibility that the outflow due to the aqueous solvent is suppressed and the hydrophobicity are improved. Since the action of water molecules on the ester group part is blocked by the hydrophobic group, it is less likely to be hydrolyzed even in products using an aqueous solvent, improving stability and possibly contributing to the improvement of residual aroma. (However, the present invention is not limited to the above principle).

As a result of sustained release, the diester compound (perfume precursor) of the present invention has a fragrance derived from the cyclohexanol derivative part represented by R ₁ —OH and the fragrance compound represented by R—OH. However, it is preferable that the scent is derived from only the fragrance compound represented by R—OH.

The diester compound (perfume precursor) of the present invention can enhance the residual aroma of the aroma of these articles by incorporating the perfume composition containing itself or the perfume composition containing the same into various articles. Details will be described later.

(Cyclohexanol or its derivative usable for the diester compound of the present invention)
Cyclohexanol or a derivative thereof that can be used in the diester compound of the present invention (or the fragrance precursor of the present invention) is arbitrary within the range shown below. That is, in the above formula A, R ₁ represents a residue obtained by removing a hydroxyl group from cyclohexanol represented by R ₁ —OH or a derivative thereof, and R ₂ and R ₃ each independently represent hydrogen or a carbon number of 1 to 4 Represents a linear or branched alkyl group.

Preferably, the cyclohexanol represented by R ₁ —OH or a derivative thereof is, but not limited to, menthol or cyclohexanol.

Note that in this specification, cyclohexanol itself and cyclohexanol derivatives including menthol and the like may be collectively referred to as “cyclohexanol derivatives”.

(Aroma compounds usable for the diester compound of the present invention)
The fragrance compound that can be used for the diester compound of the present invention (or the fragrance precursor of the present invention) is not particularly limited as long as it is an fragrance compound having one or more hydroxyl groups. In the present specification, the fragrance compound means a compound capable of causing an organism having an olfactory sense such as human, animal, or insect to perceive the scent of the fragrance compound.

ㆍThe fragrance compound needs to be volatile in order to have a fragrance, and generally, those having a molecular weight of about 350 or less are used as fragrance compounds in perfumes. Therefore, the upper limit of the carbon number is about 20 or less, and the lower limit is generally 2 or 3. Usually, the carbon number of the fragrance compound usable in the fragrance composition is in the range of 2 to 20. In the present invention, the number of carbon atoms of the fragrance compound is preferably in the range of 2 to 20, more preferably in the range of 3 to 15, further preferably in the range of 4 to 12, and further preferably in the range of 5 to 10.

The fragrance compound that can be used in the fragrance precursor of the present invention may be a linear, branched, or cyclic saturated or unsaturated aliphatic alcohol, or an aromatic alcohol. For example, 10-undecenol, 1-undecanol, 1-octanol, 1-dodecanol, 1-nonanol, 2,4-dimethyl-3-cyclohexene-1-methanol, 2,6-dimethoxyphenol, 2-undecanol, 2-ethoxy. -P-cresol, 3,6-dimethyl-3-octanol, 3-phenylpropyl alcohol, 3-methoxy-m-cresol, 4-ethylguaiacol, 4-tunanol, 4-hydroxybenzyl alcohol, 4-hydroxybenzaldehyde, 6 -Canphenol, pt-butylcyclohexanol, p-ethylphenol, tert-butylhydroquinone dimethyl ether, trans-2-hexenol, cis-3-hexenol, trans-3-hexenol, α-phenalkyl alcohol, anis alcohol, Amylcinnamic alcohol, ambrinol, isoeugenol, isoborneol, ethyl vanillin, ethyl linalool, eugenol, auranthiol, carvacrol, carveol, guaiacol, cumin alcohol, cresol, geraniol, salicylaldehyde, santalinol, santalex (registration Trademark), Sandalore (registered trademark), citronellol, dihydrolinalool, dihydroeugenol, dihydroterpineol, dihydromyrcenol, shogaol, zingerone, cinnamic alcohol, styralyl alcohol, sesamol, cedrenol, cedrol, terpineol, thymol, chavicol. , Timbelol, tetrahydromyrcenol, tetrahydrolinalol, terpineol, nerol, nerolidol, vacdanol, patchouli alcohol, vanillyl alcohol, vanillin, hydroxycitronellol, hydratropa alcohol, hinokitiol, piperonyl alcohol, farnesol, phenethyl alcohol, phenoxy Examples include, but are not limited to, ethyl alcohol, prenol, vetiverol, perilla alcohol, benzyl alcohol, polysanthol, borneol, matsutakeol, myrcenol, myrtenol, mugol, raspberry ketone, lavandulol, linalool.

Among them, aroma compounds having a phenolic hydroxyl group are preferable. More preferably, the OH portion of the fragrance compound represented by R—OH in Formula A, that is, the hydroxyl group that forms an ester bond with one carboxyl group of the dicarboxylic acid is a phenolic hydroxyl group. Examples of suitable phenolic compounds include, but are not limited to, vanillin, raspberry ketone, eugenol and the like.

In addition, examples of suitable aroma compounds belonging to aliphatic alcohols include, but are not limited to, cis-3-hexenol and tetrahydrolinalool.

(Method for obtaining diester compound of the present invention)
The method for obtaining the diester compound of the present invention (or the fragrance precursor of the present invention) is arbitrary. For example, it can be produced by a synthetic method including the following reactions, but is not limited to this method.
Reaction (1) Reaction for synthesizing monoester of cyclohexanol or its derivative represented by R ₁ -OH and dicarboxylic acid or its carboxylic acid chloride (acid chloride) (2) Cyclohexanol obtained in reaction (1) Specific examples of reactions (1) and (2) for obtaining a diester of a monoester or a carboxylic acid chloride (acid chloride) of its derivative and dicarboxylic acid and an aroma compound having a hydroxyl group represented by R—OH The reaction conditions and reagents are arbitrary as long as the desired reaction product can be obtained, and examples thereof include, but are not limited to, the following.

Regarding reaction (1), general reaction conditions for esterification of carboxylic acid and alcohol may be adopted. The esterification reaction between the dicarboxylic acid monoester and the aroma compound having a hydroxyl group uses an acid or base catalyst (eg, N,N-dimethyl-4-aminopyridine (DMAP)), and various condensing agents (eg, diisopropylcarbodiimide ( DIC)). Alternatively, as the cyclohexanol derivative-dicarboxylic acid monoester, a commercially available product may be used as appropriate, for example, mono-1-menthyl glutarate is commercially available.

Methods for synthesizing carboxylic acid chlorides are well known. For example, if necessary, in the presence of a catalyst, carboxylic acid and thionyl chloride, oxalyl chloride, phosphorus trichloride, phosphorus pentachloride, sulfuryl chloride and the like (preferably, chloride (Thionyl or oxalyl chloride). An example of the catalyst is N,N-dimethylformamide (DMF), which can produce chloride under milder conditions.

Regarding the esterification in the reaction (2), any of the above dicarboxylic acid monoesters and carboxylic acid chlorides may be used. As in the reaction (1), a general carboxylic acid or acid chloride and an alcohol are esterified. The conditions may be adopted, and the esterification reaction of the dicarboxylic acid monoester and the aroma compound having a hydroxyl group uses an acid or base catalyst (eg, N,N-dimethyl-4-aminopyridine (DMAP)) to appropriately perform various condensations. It can be carried out in the presence of an agent (for example, diisopropylcarbodiimide (DIC)). The ester reaction of a carboxylic acid chloride and a hydroxyl group can be usually performed in the presence of a base such as pyridine.

Reactions (1) and (2) may be performed simultaneously, or reaction (1) may be followed by reaction (2).

(Fragrance composition of the present invention)
The fragrance composition of the present invention contains a predetermined amount of the diester compound of the present invention (or the fragrance precursor of the present invention) and can be blended into various articles. Examples of the goods include consumer goods such as cosmetics, health and hygiene products, pharmaceuticals, foods and drinks, and various other types of favorite products (details will be described later). The form of the flavor composition of the present invention is not particularly limited, and examples thereof include a water-soluble flavor composition, an oil-soluble flavor composition, an emulsified flavor composition, a powder flavor composition, and an encapsulated flavor composition. When it is desired to further improve the residual aroma, a known technique for improving the residual aroma may be used, and examples thereof include a known encapsulation technique.

The concentration of the diester compound (perfume precursor) of the present invention in the perfume composition of the present invention, the fragrance of the fragrance compound, the object of use of the fragrance composition, the fragrance of the fragrance composition, the degree of desired residual aroma, etc. It can be arbitrarily determined according to the purpose. Usually, it may be in the range of 1 ppb to 10%, but is not limited thereto. In the present specification, “to” means a range including the lower limit value and the upper limit value, and the concentration means the mass concentration unless otherwise specified.

Further, the perfume composition of the present invention may contain any other compound or component in addition to the diester compound (perfume precursor) of the present invention.

Examples of such compounds or components include various kinds of fragrance compounds or fragrance compositions, oil-soluble pigments, vitamins, functional substances, plant extracts, animal and plant proteins, solvents and the like. For example, "Patent Office Bulletin, Well-Known and Conventional Techniques Collection (Flavor) Part II Food Flavor, Issued on January 14, 2000", "Survey on Use of Food Aroma Compounds in Japan" (FY 2000 Health Science Research Report, Japan Perfume Industry Association, published in March 2001), and "Synthetic perfume chemistry and product knowledge" (issued on December 20, 2016, supplemented new edition, edited by Synthetic Perfume Editing Committee, Chemical Industry Daily) The natural essential oils, natural fragrances, synthetic fragrances and the like that have been used can be mentioned. It can be arbitrarily determined according to the fragrance and flavor of the fragrance composition and its blending target.

(Consumable Goods in which the Diester Compound (Perfume Precursor) of the Present Invention or Perfume Composition can be Blended) The diester compound of the present invention can be used as a perfume precursor by itself or as a component contained in the perfume composition as an optional consumer product. Can be blended into. The consumer goods are not particularly limited, but preferred examples include cosmetics, health and hygiene products, pharmaceuticals, foods and drinks, and various other types of favorite products.

As a more specific example, for cosmetics, perfumes such as cologne, eau de toilette, eau de parfum, parfum, etc.; hair care products such as shampoo, conditioner, hair styling products (hair cream, pomade, etc.); foundation, lipstick, lip balm, Cosmetics such as lip gloss, lotion, cosmetic emulsion, cosmetic cream, cosmetic gel, beauty essence, and packs; deodorant products such as antiperspirant sprays, deodorant sheets, deodorant creams, deodorant sticks; inorganic salts, cooling -Based, carbon dioxide-based, skin care-based, enzyme-based, herbal medicine-based bath agents; suntan cosmetics such as suntan products and sunscreen products; facial cleansers such as face soaps and facial creams, body soaps and body soaps, laundry Cleaning agents such as soap for laundry, laundry detergent, disinfectant detergent, deodorant detergent, softener, kitchen detergent, cleaning detergent; health and hygiene materials such as toothpaste, tissue paper, toilet paper, etc. Aromatic deodorants for space, aroma deodorants for various items such as daily necessities and furniture, aromatics such as room fragrances; insect repellents, insect repellents, insecticides and other harmful insect repellents, etc. However, the present invention is not limited to these. In particular, consumer goods in a use form in which the fragrance precursor of the present invention can be attached to articles such as cloth, skin, and hair are preferable. As the article, an article having a fibrous structure on the surface is preferable, and various fiber products such as towels, hand towels, cloths, bedding, curtains, rugs, and clothing are preferable examples. For food and drink, rice crackers such as rice crackers and rice cakes, sweets containing bean paste, uiro, mutton, jelly, castella, biscuits, cookies, pies, cakes, chips and other baked or fried confectionery, pudding, cream, chocolate, gum. Sweets such as caramel, candy, dips, spreads and pastes; breads; noodles such as udon, buckwheat noodles and noodles; cooked rice such as sushi, gome rice, fried rice and pilaf; Chinese foods such as dumplings, shumai and spring rolls Powdered foods such as okonomiyaki and takoyaki; pickles and pickled foods; processed foods and drinks of seafood; processed foods and drinks using livestock meat; salt, seasoning salt, soy sauce, miso, sprinkles, tea pickles, Margarine, mayonnaise, dressing, vinegar, sauces, sauces, ketchups, sauces, curry roux, stew base, soup base, dashi stock, complex seasoning, fresh mirin, seasonings such as mixed flour; cheese, Dairy products such as yogurt and butter; stewed vegetables such as stewed vegetables, oden and pots; take-away bento ingredients and side dishes; fruit juice, fruit juice drinks or juice-containing soft drinks, fruit pulp and fruit drinks with fruit grains; vegetables Beverages containing vegetables, foods and drinks containing vegetables such as soups; sports drinks, honey drinks, nutritional supplement drinks, lactic acid bacteria drinks, coffee drinks, cocoa drinks, green tea, black tea, oolong tea, soft drinks, cola drinks, fruit juice drinks, milk drinks, Favorite beverages such as beer-taste beverages; beverages containing crude drugs and herbs; wine, beer, chu-hi, cocktail drinks, sparkling liquor, fruit liquor, condiment liquor, and other brewed liquors such as so-called "third beer" (sparkling) Or alcoholic beverages such as liqueur (foaming); and the like, but not limited thereto. Other luxury items include, but are not limited to, tobacco and electronic cigarettes.

The fragrance tone that can be used is not particularly limited, and may be arbitrarily determined according to the fragrance, use, blending target, etc. of the fragrance compound contained in the fragrance precursor of the formula A of the present invention or the fragrance composition containing the same. Good. For example, it can be used in a vanilla tone, a citrus tone, a floral tone, a fruity tone, a green tone, a moss tone, a herbal tone, and the like. An example of a preferable fragrance tone is, but not limited to, a vanilla tone.

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

[Example 1]
As described below, various diester compounds (perfume precursors) of the present invention were synthesized.

(1) Synthesis of fragrance precursor 1: 4-formyl-2-methoxyphenyl 1-menthyl glutarate 4-formyl-2-methoxyphenyl 1-menthyl glutarate of the following formula (1) is synthesized according to the following reaction route (1). did.

Mono-l-menthyl glutarate (10.0 g, 37 mmol) was charged into a 50 mL flask, and while heating to 40° C. and stirring, 4.4 g (37 mmol) of thionyl chloride was added dropwise to obtain acid chloride. Then, vanillin (4.6 g, 0.03 mol) and pyridine (10.0 g, 0.125 mol) were charged into a 50 mL two-necked flask equipped with a calcium chloride tube, and the mixture was stirred under ice-water cooling. A solution of the acid chloride (7.4 g, 0.025 mol) obtained in the previous step in n-hexane (10 g) was added dropwise over 0.5 hour under ice-water cooling. After stirring for 1 hour under ice-water cooling, the mixture was stirred overnight at room temperature. The reaction solution was poured into ice water and extracted with ether. The obtained ether layer was washed successively with diluted hydrochloric acid, multi-layered water and saturated saline, and dried over anhydrous magnesium sulfate. After concentration under reduced pressure, the obtained residue (10.2 g) was purified by silica gel column chromatography (48 mm id×20 cm L, n-hexane:ethyl acetate=5:1) to give the desired product 4- Formyl-2-methoxyphenyl 1-menthyl glutarate (8.8 g) was obtained (yield 87%). The physical properties of the obtained compound are shown below.

Physical property data of 4-formyl-2-methoxyphenyl 1-menthyl glutarate:
¹ H-NMR (400 MHz, CDCl ₃ ): δppm
9.93(s, 1H), 7.47(d, J=2.0Hz, 1H), 7.44(dd, J=8.0, 2.0Hz, 1H), 7.21(d, J =8.0 Hz, 1H), 4.71 (dt, J=11, 4.4 Hz, 1H), 3.88 (s, 3H), 2.65 (br.t, J=6.8 Hz, 2H) , 2.45 (br.t, J=8.0 Hz, 2H), 2.00 to 1.94 (m, 1H), 1.95 (d.sept, J=7, 2.8 Hz, 1H), 1.8 to 1.7 (m, 2H), 1.68 to 1.61 (m, 2H), 1.52 to 1.40 (m, 1H), 1.40 to 1.32 (m, 1H) ), 1.06 to 0.98 (m, 1H), 0.95 (q, J = 11Hz, 1H), 0.89 (d, J = 7Hz, 3H), 0.86 (d, J = 7Hz) , 3H), 0.88 to 0.79 (m, 1H), 0.74 (d, J=7Hz, 3H)
¹³ C-NMR (100 MHz, CDCl ₃ ): δppm
191.04, 172.39, 170.44, 151.88, 144.92, 135.19, 124.78, 123.36, 110.71, 74.30, 56.02, 47.00, 40. 94, 34.21, 33.39, 33.01, 31.36, 26.28, 23.38, 22.01, 21.75, 20.30, 16.28.
IR (liquid film method): 2950, 2875, 1765, 1730, 1700, 1605, 1500, 1455, 1420, 1385, 1280, 1205, 1130, 1030, 720 cm ^-1

(2) Synthesis of perfume precursor 2: 4-formyl-2-methoxyphenyl 1-menthyl succinate 4-formyl-2-methoxyphenyl 1-menthyl succinate of the following formula (2) is synthesized according to the following reaction route (2). did.

Physcool® 2.94 g (11.5 mmol), vanillin 1.53 g (10.1 mmol) and catalytic amount of N,N-dimethyl-4-aminopyridine (DMAP) were dissolved in CH ₂ Cl ₂ (7 mL). Under ice cooling, 1.89 g (15.0 mmol) of N,N-diisopropylcarbodiimide (DIC) was added dropwise, and the mixture was stirred at room temperature for 22.5 hours. The colorless precipitate was filtered off, washed with ethyl acetate, the filtrate and the washing solution were combined, washed with saturated brine, dried over anhydrous magnesium sulfate, and the solvent was distilled off with an evaporator to obtain a residue (4.70 g). It was This was purified by silica gel column chromatography (48 mm id×20 cm L, n-hexane:ethyl acetate=5:1) to obtain the desired product, 4-formyl-2-methoxyphenyl 1-menthyl succinate (3 .79 g) was obtained (yield 97%). The physical properties of the obtained compound are shown below.

Physical property data of 4-formyl-2-methoxyphenyl 1-menthyl succinate:
¹ H-NMR (400 MHz, CDCl ₃ ): δppm
9.92 (s, 1H), 7.47 (d, J=2.0Hz, 1H), 7.45 (dd, J=8.0, 2.0Hz, 1H), 7.21 (d, J) =8.0 Hz, 1H), 4.71 (dt, J=11, 4.4 Hz, 1H), 3.87 (s, 3H), 2.92 (br.t, J=6.8 Hz, 2H) /2.71 (br.t, J=6.8 Hz, 2H)), 2.00 to 1.94 (m, 1H), 1.84 (d.sept, J=7, 2.8 Hz, 1H) , 1.68 to 1.61 (m, 2H), 1.52 to 1.40 (m, 1H), 1.40 to 1.32 (m, 1H), 1.08 to 0.98 (m, 1H), 0.95 (q, J = 11Hz, 1H), 0.87 (d, J = 7Hz, 3H), 0.85 (d, J = 7Hz, 3H), 0.88 to 0.79 ( m, 1H), 0.72 (d, J=7Hz, 3H)
¹³ C-NMR (100 MHz, CDCl ₃ ): δppm
191.01, 171.43, 169.86, 151.88, 144.83, 135.17, 124.72, 123.39, 110.72, 74.74, 56.05, 46.95, 40. 82, 34.17, 31.34, 29.34/29.01, 26.22, 23.37, 21.98, 20.71, 16.26.
IR (liquid film method): 2950, 2860, 2720, 1770, 1720, 1700, 1600, 1500, 1460, 1420, 1380, 1270, 1195, 1120, 1030, 990, 980, 880, 790, 740 cm ^-1

(3) Synthesis of perfume precursor 3: 4-formyl-2-methoxyphenyl 1-menthyl adipate 4-formyl-2-methoxyphenyl 1-menthyl adipate of the following formula (3) is synthesized according to the following reaction pathway (3). did.

2.53 g (16.2 mmol) of 1-menthol and 2.37 g (16.2 mmol) of adipic acid were dissolved in a mixed solvent of CH ₂ Cl ₂ (10 mL) and N,N-dimethylformamide (DMF) (7 g) and iced. Under cooling, 3.06 g (24.2 mmol) of N,N-diisopropylcarbodiimide (DIC) was added dropwise, and after stirring at room temperature for 24 hours, 0.40 g (3 of N,N-dimethyl-4-aminopyridine (DMAP)) was added. .3 mmol) was added and the mixture was stirred for 3.5 hours while heating to 58°C. 2.47 g (16.2 mmol) of vanillin and 2.04 g (16.2 mmol) of N,N-diisopropylcarbodiimide (DIC) were added, and the mixture was stirred at 58° C. for 7.5 hours and at room temperature for 62 hours. The reaction was stopped here, the precipitate was filtered off and washed with ethyl acetate. The filtrate and the washing solution were combined, washed with saturated saline, dried over anhydrous magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain a residue (8.80 g). This was purified by silica gel column chromatography (48 mm id×34.5 cm L, n-hexane:ethyl acetate=5:1) to obtain the desired product, 4-formyl-2-methoxyphenyl 1-menthyl adipate. (1.75 g) was obtained (yield 26%). The physical properties of the obtained compound are shown below.

Physical property data of 4-formyl-2-methoxyphenyl 1-menthyl adipate:
¹ H-NMR (400 MHz, CDCl ₃ ): δppm
9.90 (s, 1H), 7.45 (d, J=1.6Hz, 1H), 7.44 (dd, J=7.6, 1.6Hz, 1H), 7.17 (d, J =7.6 Hz, 1H), 4.66 (dt, J=11,4.5 Hz, 1H), 3.86 (s, 3H), 2.60 (br.t, J=7.0 Hz, 2H) , 2.33 (br.t, J=6.8 Hz, 2H), 1.98 to 1.92 (m, 1H), 1.83 (d.sept, J=6.8, 2.8 Hz, 1H) ), 1.8 to 1.7 (m, 4H), 1.68 to 1.60 (m, 2H), 1.52 to 1.39 (m, 1H), 1.37 to 1.29 (m , 1H), 1.07 to 0.97 (m, 1H), 0.93 (q, J=12 Hz, 1H), 0.86 (d, J=6.8 Hz, 3H)/0.85 (d , J=6.8 Hz, 3H), 0.87 to 0.77 (m, 1H), 0.72 (d, J=6.8 Hz, 3H)
¹³ C-NMR (100 MHz, CDCl ₃ ): δppm
190.98, 172.76, 170.65, 151.88, 144.92, 135.10, 124.68, 123.31, 110.68, 74.05, 55.96, 46.93, 40. 88, 34.17, 34.17, 33.52, 31.29, 26.21, 24.29/24.26, 23.32, 21.96, 20.69, 16.22.
IR (liquid film method): 2950, 2860, 2730, 1770, 1720, 1700, 1600, 1500, 1460, 1420, 1390, 1270, 1145, 1120, 1030, 990, 910, 790, 730 cm ^-1

(4) Synthesis of perfume precursor 4: 4-formyl-2-methoxyphenyl 1-menthyl sebacate 4-formyl-2-methoxyphenyl 1-menthyl sebacate of the following formula (4) is synthesized according to the following reaction route (4). did.

1.61 g (10.3 mmol) of l-menthol and 1.57 g (10.3 mmol) of vanillin were dissolved in CH ₂ Cl ₂ (10 mL), 4.07 g (51.5 mmol) of pyridine was added, and chloride was further added under ice cooling. 2.62 g (11.0 mmol) of Sebacoil was added, and the mixture was stirred at 0° C. for 20 minutes and then at room temperature for 19 hours. Water was added to the reaction solution to dissolve the precipitate, which was extracted with ether. The organic layer was washed with a 1N HCl aqueous solution, a saturated sodium hydrogen carbonate aqueous solution, and saturated saline, dried over anhydrous magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain a residue (4.78 g). This was purified by silica gel column chromatography (48 mm id×19 cm L, n-hexane:ethyl acetate=20:1 to 5:1), and 4-formyl-2-methoxyphenyl l was added at 5:1. -Mentyl sebacate (1.20 g) was obtained (yield 25%). The physical properties of the obtained compound are shown below.

Physical property data of 4-formyl-2-methoxyphenyl 1-menthyl sebacate:
¹ H-NMR (400 MHz, CDCl ₃ ): δppm
9.93(s, 1H), 7.47(d, J=1.7Hz, 1H), 7.45(dd, J=7.6, 1.7Hz, 1H), 7.19(d, J =7.6 Hz, 1H), 4.65 (dt, J=11, 4.7 Hz, 1H), 3.87 (s, 3H), 2.58 (br.t, J=7.6 Hz, 2H) , 2.26 (br.t, J=7.6 Hz, 2H), 1.99 to 1.93 (m, 1H), 1.84 (d.sept, J=6.8, 2.8 Hz, 1H) ), 1.74 (br. quint, J=7.7 Hz, 2H), 1.7 to 1.6 (m, 2H), 1.60 to 1.55 (m, 2H), 1.5 to 1 .35 (m, 2H), 1.35 to 1.3 (m, 8H), 1.08 to 0.97 (m, 1H), 0.93 (q, J=12Hz, 1H), 0.88 (
d, J=6.8 Hz, 3H), 0.87 (d, J=6.8 Hz, 3H), 0.9 to 0.79 (m, 1H), 0.73 (d, J=6.8 Hz) , 3H)
¹³ C-NMR (100 MHz, CDCl ₃ ): δppm
191.08, 173.40, 171.18, 151.98, 145.07, 135.10, 124.80, 123.42, 110.71, 73.88, 56.04, 47.00, 40. 95, 34.71, 34.25, 33.95, 31.36, 29.10/29.08/29.05/28.94, 26.22, 25.08/24.87, 23.37, 22.02, 20.77, 16.27

(5) Synthesis of perfume precursor 5: 1-menthyl tetrahydrolinalyl glutarate 1-menthyl tetrahydrolinalyl glutarate of the following formula (5) was synthesized according to the following reaction route (5).

2.70 g (9.99 mmol) of mono-1-menthyl glutarate was dissolved in methylene chloride (6.5 mL), 1.58 g (9.98 mmol) of tetrahydrolinalool and N,N-dimethyl-4-aminopyridine (DMAP) 0.15 g (1.2 mmol) was added, and N,N-diisopropylcarbodiimide (DIC) 1.89 g (15.0 mmol) was added dropwise under ice cooling, and the mixture was placed in a water bath at 35° C. for 6 hours and then at room temperature for 63 hours. Stir for 5 hours. At this point the reaction was stopped, the precipitate was filtered off and washed with ethyl acetate. The filtrate and the washing solution were combined, washed with saturated saline, dried over anhydrous magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain a residue (5.12 g). This was purified by silica gel column chromatography (48 mm id×19.5 cm L, n-hexane:ethyl acetate=25:1) to obtain l-menthyl tetrahydrolinalyl glutarate (2.02 g) (yield Rate 49%). The physical properties of the obtained compound are shown below.

Physical property data of l-menthyl tetrahydrolinalyl glutarate
¹ H-NMR (400 MHz, CDCl ₃ ): δppm
4.64 (dt, J=11, 4.4 Hz, 1H), 2.29 (br.t, J=7.2 Hz, 2H), 2.24 (t, J=7.2 Hz), 1.96. Up to 1.90 (m, 1H), 1.86 (br. quint, J=7.2 Hz), 1.85 to 1.75 (m, 1H), 1.85 to 1.65 (m, 2H) , 1.8 to 1.6 (m, 2H), 1.66 to 1.58 (m, 2H), 1.52 to 1.37 (m, 2H), 1.35 to 1.3 (m, 1H), 1.33 (s, 3H), 1.24 to 1.16 (m, 2H), 1.13 to 1.08 (m, 2H), 1.06 to 0.95 (m, 1H) , 0.91 (br.q, J=11 Hz, 1H), 0.86 to 0.80 (m, 16H), 0.70 (d, J=6.8 Hz, 3H)
¹³ C-NMR (100 MHz, CDCl ₃ ): δppm
172.54, 172.07, 85.23, 74.04, 46.91, 40.86, 39.16, 37.94, 34.47, 34.19, 33.73, 31.30, 30. 82, 27.73, 26.17, 23.31, 23.28, 22.54/22.54, 21.96, 21.27, 20.71, 20.52, 16.20, 7.94.
IR (liquid film method): 2950, 2865, 1730, 1460, 1420, 1320, 1240, 1180, 1135, 1020, 980 cm ^-1

(6) Synthesis of perfume precursor 6: cis-3-hexenyl 1-menthyl glutarate A cis-3-hexenyl 1-menthyl glutarate of the following formula (6) was synthesized according to the following reaction route (6).

2.70 g (9.99 mmol) of mono-1-menthyl glutarate was dissolved in methylene chloride (6.5 mL), and 1.00 g (9.98 mmol) of cis-3-hexenol and a catalytic amount of N,N-dimethyl-4 were dissolved. -Aminopyridine (DMAP) was added, and N,N-diisopropylcarbodiimide (DIC) (1.89 g, 15.0 mmol) was added dropwise under ice cooling, and the mixture was stirred at 0°C for 40 minutes and further at room temperature for 17.5 hours. The precipitate was filtered off and washed with ethyl acetate. The filtrate and the washing solution were combined, washed with saturated saline, dried over anhydrous magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain a residue (3.92 g). This was purified by silica gel column chromatography (48 mm id×16 cm L, n-hexane:ethyl acetate=25:1) to obtain cis-3-hexenyl 1-menthyl glutarate (3.31 g) ( Yield 94%). The physical properties of the obtained compound are shown below.

Physical property data of cis-3-hexenyl 1-menthyl glutarate:
¹ H-NMR (400 MHz, CDCl ₃ ): δppm
5.50 to 5.43 (m, 1H), 5.30 to 5.24 (m, 1H), 4.65 (dt, J=11, 4.4 Hz, 1H), 4.04 (t, J =6.8 Hz, 2H), 2.36 to 2.29 (m, 6H), 2.02 (br. quint, J=7.6 Hz, 2H), 1.96 to 1.9 (m, 1H) , 1.89 (br. quint, J=7.2 Hz, 2H), 1.81 (d. sept, J=6.8, 2.8 Hz, 1H), 1.67 to 1.60 (m, 2H) ), 1.51 to 1.38 (m, 1H), 1.36 to 1.29 (m, 1H), 1.07 to 0.95 (m, 1H), 1.0 to 0.9 (m , 1H), 0.93(t, J=7.6Hz, 3H), 0.86(t, J=6.8Hz, 3H)/0.85(t, J=6.8Hz, 3H), 0 0.9 to 0.77 (m, 1H), 0.71 (d, J=6.8Hz, 3H)
¹³ C-NMR (100 MHz, CDCl ₃ ): δppm
172.93, 172.44, 134.52, 123.61, 74.12, 63.88, 46.92, 40.87, 34.19, 33.63/3.27, 31.32, 29. 67, 26.21, 23.34, 21.97, 20.71, 20.55/20.25, 16.23, 14.19
IR (liquid film method): 3010, 2955, 2925, 2870, 1735, 1460, 1420, 1385, 1365, 1305, 1240, 1175, 1140, 1060, 1135, 1015, 980 cm ^-1

(7) Synthesis of perfume precursor 7: 1-menthyl 4-(3-oxobutyl)phenyl glutarate 1-menthyl 4-(3-oxobutyl)phenyl glutarate of the following formula (7) is synthesized according to the following reaction route (7). did.

2.70 g (9.99 mmol) of mono-1-menthyl glutarate was dissolved in methylene chloride (7.5 mL), 1.64 g (9.99 mmol) of raspberry ketone and a catalytic amount of N,N-dimethyl-4-aminopyridine ( DMAP) was added, 1.89 g (15.0 mmol) of N,N-diisopropylcarbodiimide (DIC) was added dropwise under ice cooling, and the mixture was stirred at room temperature for 21 hours. The precipitate was filtered off and washed with ethyl acetate. The filtrate and the washing solution were combined, washed with saturated saline, dried over anhydrous magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain a residue (4.34 g). This was purified by silica gel column chromatography (48 mm id×17 cm L, n-hexane:ethyl acetate=10:1 to 5:1), and l-menthyl 4-(3-oxobutyl)phenyl glutarate (3 .95 g) was obtained (yield 95%). The physical properties of the obtained compound are shown below.

Physical property data of 1-menthyl 4-(3-oxobutyl)phenyl glutarate:
¹ H-NMR (400 MHz, CDCl ₃ ): δppm
7.16 (br.d, J=8.8 Hz, 2H), 6.96 (br.d, J=8.8 Hz, 2H), 4.68 (dt, J=11, 4.4 Hz, 1H) , 2.86 (t, J=7.4 Hz, 2H), 2.72 (t, J=7.4 Hz, 2H), 2.59 (t, J=7.4 Hz, 2H), 2.41( br.t, J=7.4 Hz, 2H), 2.12 (s, 3H), 2.04 (br. quint, J=7.4 Hz, 2H), 1.98 to 1.94 (m, 1H). ), 1.84 (d.sept, J=6.8, 2.8 Hz, 1H), 1.69 to 1.62 (m, 2H), 1.53 to 1.40 (m, 1H), 1 .39 to 1.32 (m, 1H), 1.09 to 0.98 (m, 1H), 0.95 (br.q, J=11 Hz, 1H), 0.88 (t, J=6. 8 Hz, 3 H)/0.86 (t, J=6.8 Hz, 3 H), 0.9 to 0.79 (m, 1 H), 0.74 (d, J=6.8 Hz, 3 H)
¹³ C-NMR (100 MHz, CDCl ₃ ): δppm
207.67, 172.37, 172.40, 148.84, 138.55, 129.24, 129.24, 121.44, 121.44, 74.28, 46.95, 45.06, 40. 89, 34.19, 33.49/33.30, 31.34, 30.07, 28.98, 26.26, 23.36, 21.99, 20.73, 20.12, 16.27.
IR (KBr tablet method): 2950, 2895, 2860, 1750, 1725, 1710, 1510, 1450, 1420, 1380, 1370, 1320, 1295, 1230, 1210, 1190, 1165, 1140, 1020, 970.

(8) Synthesis of fragrance precursor 8: Eugenyl 1-menthyl glutarate Eugenyl 1-menthyl glutarate of the following formula (8) was synthesized according to the following reaction route (8).

2.72 g (10.1 mmol) of mono-1-menthyl glutarate was dissolved in CH ₂ Cl ₂ (6.5 mL), and 1.66 g (10.1 mmol) of eugenol and a catalytic amount of N,N-dimethyl-4-amino. Pyridine (DMAP) was added, and N,N-diisopropylcarbodiimide (DIC) (1.91 g, 15.1 mmol) was added dropwise under ice cooling, and the mixture was stirred at room temperature for 20 hours. The precipitate was filtered off and washed with ethyl acetate. The filtrate and the washing solution were combined, washed with saturated saline, dried over anhydrous magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain a residue (4.78 g). This was purified by silica gel column chromatography (48 mm id×18.5 cm L, n-hexane:ethyl acetate=20:1) to obtain a purified product (3.95 g). On the other hand, the product was purified again by silica gel column chromatography (33 mm id×37 cm L, toluene:acetone=50:1 to 5:1) to obtain eugenyl 1-menthyl glutarate (3.34 g) ( Yield 80%). The physical properties of the obtained compound are shown below.

Physical property data of eugenyl l-menthyl glutarate:
¹ H-NMR (400 MHz, CDCl ₃ ): δppm
6.91 (d, J=8.0 Hz, 1H), 6.76 (d, J=2.0 Hz, 1H), 6.73 (dd, J=8.0, 2.0 Hz, 1H), 5 .93 (ddt, J=17, 10, 6.8 Hz, 1H), 5.11 to 5.04 (m, 2H), 4.68 (dt, J=11, 4.4 Hz, 1H), 3. 78 (s, 3H), 3.35 (br.d, J=6.8 Hz, 2H), 2.61 (t, J=7.2 Hz, 2H), 2.44 (br.t, J=7) .2 Hz, 2H), 2.06 (br. quint, J=7.2 Hz, 2H), 2.00 to 1.95 (m, 1H), 1.85 (d.sept, J=6.8, 2.8 Hz, 1H), 1.69 to 1.62 (m, 2H), 1.53 to 1.41 (m, 1H), 1.39 to 1.32 (m, 1H), 1.09 to 0.98 (m, 1H), 0.95 (br.q, J = 11Hz, 1H), 0.9 to 0.79 (m, 1H), 0.88 (t, J = 6.4Hz, 3H ), 0.87 (t, J=6.8 Hz, 3H), 0.74 (d, J=6.8 Hz, 3H)
¹³ C-NMR (100 MHz, CDCl ₃ ): δppm
172.41, 171.11, 150.68, 138.84, 137.83, 136.94, 122.34, 120.54, 116.04, 112.54, 74.07, 55.60, 46. 92, 40.85, 39.98, 34.15, 33.40, 32.97, 31.28, 26.17, 23.30, 21.94, 20.68, 20.36, 16.20.
IR (liquid film method): 2980, 2950, 2865, 1760, 1730, 1640, 1605, 1510, 1455, 1420, 1370, 1200, 1130, 1035, 980, 915 cm ^-1

(9) Synthesis of perfume precursor 9: Cyclohexyl 4-formyl-2-methoxyphenyl glutarate A cyclohexyl 4-formyl-2-methoxyphenyl glutarate of the following formula (9) is synthesized according to the following reaction routes (9)-1 to 2: did.

Cyclohexanol 10.27 g (102.5 mmol) was dissolved in toluene (22 g) and heated to 95°C. Then, 12.84 g (112.5 mmol) of glutaric anhydride and 0.20 g (1.1 mmol) of p-toluenesulfonic acid monohydrate (p-TsOH.H ₂ O) were added to toluene (50 g)-dimethyl ether ( The solution dissolved in the mixed solvent (7 mL) was added dropwise over 30 minutes, heating was continued at 95° C. for 5.5 hours, and the mixture was further stirred at room temperature for 13.5 hours. The reaction solution was diluted with ethyl acetate, and the organic layer was washed with a saturated NaHCO ₃ aqueous solution and saturated saline. All the organic layers were combined and dried over anhydrous magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain a residue (23.09 g). This was purified by silica gel column chromatography (47 mm id x 45 cm L, n-hexane-ethyl acetate=3:1 to 2:1) to obtain 17.59 g (yield 80%). This was used as a starting material for the next reaction route (9)-2.

Next, 3.00 g (14.0 mmol) of the starting material of reaction pathway (9)-2, 2.13 g (14.0 mmol) of vanillin, and DMAP (catalytic amount) were dissolved in dichloromethane (3-4 mL), and the mixture was cooled with ice. 2.65 g (21.0 mmol) of DIC was added dropwise, and the mixture was stirred at 2° C. for 10 minutes and then at room temperature for 18 hours. The precipitate was filtered off and washed well with ethyl acetate. The filtrate and the washing solution were combined, washed with saturated brine, dried over anhydrous magnesium sulfate, and the solvent was distilled off with an evaporator to obtain a residue (5.48 g). This was purified by silica gel column chromatography (47 mm id x 26 cm L, n-hexane-ethyl acetate = 15:1 to 4:1), and cyclohexyl 4-formyl-2-methoxyphenyl glutarate (4.55 g) Was obtained (yield 93%). The physical properties of the obtained compound are shown below.

Physical property data for cyclohexyl 4-formyl-2-methoxyphenyl glutarate:
¹ H-NMR (400 MHz, CDCl ₃ ): δppm
9.90 (s, 1H), 7.45 (d, J=1.6Hz, 1H), 7.43 (dd, J=8.0, 1.6Hz, 1H), 7.17 (d, J =8.0 Hz, 1H), 4.75 (tt, J=8.8, 4.3 Hz, 1H), 3.85 (s, 3H), 2.65 (t, J=7.4 Hz, 2H) , 2.43 (t, J=7.4 Hz, 2H), 2.05 (br. quint, J=7.4 Hz, 2H), 1.85 to 1.79 (m, 2H), 1.73 to 1.65 (m, 2H), 1.54 to 1.46 (m, 1H), 1.43 to 1.28 (m, 4H), 1.26 to 1.17 (m, 1H)
¹³ C-NMR (100 MHz, CDCl ₃ ): δppm
190.97, 172.19, 170.39, 151.81, 144.85, 135.11, 124.67, 123.29, 110.67, 72.67, 55.95, 33.36, 32. 92, 31.57/31.57, 25.27, 23.65/23.65, 20.19
IR (liquid film method): 2938, 2855, 2720, 1760, 1725, 1700, 1600, 1500, 1450, 1420, 1380, 1270, 1120, 1030, 910, 870, 830, 780, 735 cm ^-1

[Example 2] Residual fragrance property of the fragrance precursor of the present invention In this example, a test was performed on the fragrance property of various fragrance precursors. First, a commercially available fragrance-free softening agent is prepared as a base material, and the softening material base material is used to form one of the fragrance precursors synthesized in Example 1 having a phenolic hydroxyl group or the fragrance precursor. The fragrance compound alone (that is, the molecule represented by R—OH in Formula A) was blended so that the amount thereof was 1% based on the total mass of the base material. Next, 0.5 g of this softening agent was dissolved in 1.5 L of water (20° C.) (diluted 3000 times), a 100% cotton towel was immersed therein, and the mixture was stirred 20 times by hand and then left for 10 minutes. Then, the water on the towel was squeezed by hand and suspended in a room exposed to sunlight. At this time, the towels were divided into a group in which they were left suspended for 24 hours and a group in which hot air at 50 to 60° C. was applied for 30 minutes.

A sensory evaluation was performed on the aroma felt from each of the towels thus obtained. In the sensory evaluation, 4 to 7 trained perfumers sniffed the scent of the towel, and the strength of the scent was compared with the scent compound alone, with the scent intensity of the single scent compound as 1 point. Was scored according to the following criteria.
1 point: equally felt 2 points: slightly strongly felt 3 points: strongly felt 4 points: clearly strongly felt 5 points: very strongly felt The above average results are shown in Table 1 below. In Table 1, "indoor" means a towel left for 24 hours in a room exposed to the above-mentioned sunlight, and "heat" means a towel exposed to hot air of 50 to 60°C for 30 minutes.

As shown in Table 1, it was confirmed that each of the fragrance precursors of the present invention has higher residual aroma than the fragrance compound alone. In each case, no menthol-like or cyclohexanol-like scent was felt.

As described above, the fragrance precursor of the product of the present invention exhibited superior residual fragrance property due to the sustained release of the fragrance compound as compared with the fragrance compound alone. Therefore, it was confirmed that the use of the cyclohexanol derivative as in the present invention can give excellent residual odor.

[Example 3] Persistence confirmation of fragrance (analytical evaluation)
The superior residual aroma of the fragrance precursor of the present invention was confirmed by conducting a component analysis as follows.

(1) Preparation of Towel for Analysis 4-formyl-2-methoxyphenyl 1-menthyl glutarate, which is the fragrance precursor of the present invention obtained in Example 1 (1), was added to the softener base described in Example 2. Was added to the total amount of the softener base material so that the concentration would be 1% by mass. Similarly, vanillin alone was blended so as to have a concentration of 1 mass% with respect to the total amount of the softener base material. In this way, the following softeners A and B were prepared.
Softener A: Softener containing the fragrance precursor of the present invention (4-formyl-2-methoxyphenyl 1-menthyl glutarate (hereinafter also referred to as MVG)) Softener B: Softener containing vanillin alone and Examples. Immersion and hot air treatment (hot air at 50 to 60° C. for 30 minutes) were carried out in the same manner as in 2, and the following towel samples A and B were prepared.
Towel sample A: Towel using softener A (containing 1% of MVG) (product of the present invention)
Towel sample B: Towel using softener B (containing 1% of vanillin alone) (comparative product)
(2) Analysis and Results Each compound remaining in towel samples A and B was quantified. Below, the procedure at the time of preparing the sample liquid for analysis is shown.

[Sample solution preparation procedure]
1) Sample towels A and B were cut into 8 equal parts with scissors 2) 1 L open column was packed with the cut towel folded in 4 3) Tetrahydrofuran (THF) (500 mL) was charged into the column 4) It was left standing for 1 hour, and was subjected to immersion extraction. 5) The column cock was opened, and THF was recovered. 6) The towel was pressed for 5 minutes by a pump from above the column, soaked in the towel and not recovered in 5). THF was squeezed out, and the collected 7) THF collected in 5) and 6) were combined to form a collected liquid 1. 8) The above operations (3 to 5) were repeated two more times to obtain a collected liquid 2 and a collected liquid 3. 9) The obtained collection liquid for analysis was obtained by combining the collection liquids 1 to 3 as the collection liquid for analysis.

[Measurement of each compound by HPLC-PDA method]
Preparation of standard solution 4-formyl-2-methoxyphenyl 1-menthyl glutarate (MVG) and vanillin were weighed accurately in a volumetric flask, and the volume was adjusted to 50% with tetrahydrofuran (THF) aqueous solution. Was appropriately and precisely diluted to prepare a standard solution.
HPLC measurement sample preparation A THF solution in which a towel was extracted was precisely weighed into a volumetric flask as appropriate, and after measuring with 50% THF, a polytetrafluoroethylene (PTFE) membrane filter (Laborabo Company, pore size 0. 45 μm) treatment was performed. This prepared solution was subjected to HPLC analysis.
HPLC-PDA measurement conditions Model: SHIMADZU PROMINENCE (Shimadzu)
Column: LunaOmega C18 (Phenomenex)
Inner diameter 2.1 mm x length 150 mm, particle diameter 1.6 μm
Column temperature: 40℃
Mobile phase: A solution... Water: Phosphoric acid=1000:1, B solution... Acetonitrile: Phosphoric acid=1000:1
Gradient conditions: (A):(B)=90:10 (0 minutes), 10:90 (12 minutes) to 10:90 (18 minutes)
Flow rate: 0.45 mL/min
Injection volume: 2 μL
Measurement time: 25 minutes Detector: PDA (MVG detection wavelength: 260 nm, vanillin detection wavelength 300 nm)
From the obtained analysis results, the adsorption rate on the towel and the amount of sustained release vanillin were calculated. The results will be described below with reference to FIGS.

(I) Adsorption rate to towel Fig. 1 is a diagram showing the adsorption rate of MVG (perfume precursor of the present invention) or vanillin to a towel. The adsorption rate was calculated by the following formula.

Adsorption rate (%) on towel = (A)/(B) x 100
(A) Total of the amounts of the perfume precursor adsorbed on the towel + the amount of vanillin in terms of moles (B) 5 mg (amount of the softener used×1% (blending ratio))/molecular weight of the perfume precursor (of the perfume precursor Number of moles added)
Each value is the sum of the amounts in the recovered liquids 1 to 3, and the amount in each recovered liquid is calculated by multiplying the concentration of the compound measured by HPLC by the weight of the recovered liquid. .. Further, after the perfume precursor (MVG) of the present invention was adsorbed on the towel, it was decomposed during the drying of the towel to gradually release vanillin, and vanillin detected from the towel was also adsorbed on the towel before being left indoors. It was assumed that it was present in the precursor, and calculated by the above formula.

As shown in FIG. 1, it was confirmed that the fragrance precursor of the present invention having a cyclohexane structure was more easily adsorbed on the towel than vanillin alone. That is, it was considered that the cyclohexane structure might have an effect of improving the adsorption rate to the article. The low adsorption rate of vanillin is considered to be because vanillin has a relatively high water solubility, and thus it is difficult for the vanillin to remain in the towel if it is simply blended in the softener base material.

(Ii) Sustained release vanillin amount FIG. 2 is a diagram showing the sustained release vanillin amount. The sustained release vanillin amount is the total amount (mg) of vanillin contained in the above-mentioned collected liquids 1 to 3, that is, it is released from the perfume precursor (MVG) of the present invention adsorbed on the towel and adsorbed on the towel. It can be regarded as the amount of vanillin released from the towel as the amount of vanillin (the present invention product) or the amount of vanillin adsorbed on the towel itself (comparative product), and can be used as an index of residual fragrance.

Each value is the sum of the amounts in the recovered liquids 1 to 3, and the amount in each recovered liquid is calculated by multiplying the concentration of the compound measured by HPLC by the weight of the recovered liquid. ..

As shown in FIG. 2, it was confirmed that the perfume precursor (MVG) of the present invention has a significantly higher sustained release vanillin amount than vanillin alone.

As shown above, it was confirmed not only by the sensory evaluation of Example 2 but also by the analytical value that the fragrance precursor of the present invention exhibited excellent residual odor. It is considered that the perfume precursor of the present invention has remarkably excellent residual fragrance property due to excellent adsorption property to an article, excellent release rate and the like.

Claims (7)

1. A diester compound represented by the following formula A:
   

   

   [In the formula A, R represents a residue obtained by removing a hydroxyl group from an aroma compound represented by R-OH, n represents an integer of 2 to 11, and R ₂ and R ₃ each independently represent hydrogen or the number of carbon atoms. It represents a linear or branched alkyl group of 1 to 4. (However, the case where n is 2 to 11 and the compounds represented by R—OH and R ₁ —OH are both l-menthol.)]
2. The diester compound according to claim 1, wherein the compound represented by R ₁ -OH is menthol or cyclohexanol.
3. The diester compound according to claim 1 or 2, wherein the aroma compound represented by R-OH has 4 to 12 carbon atoms.
4. The diester compound according to any one of claims 1 to 3, wherein in the fragrance compound represented by R-OH, the OH is a phenolic hydroxyl group.
5. A fragrance composition comprising the diester compound according to any one of claims 1 to 4.
6. A consumer product containing the diester compound according to any one of claims 1 to 4 or the fragrance composition according to claim 5.
7. A method for imparting or enhancing the residual aroma of consumer goods, which comprises blending the diester compound according to any one of claims 1 to 4 or the fragrance composition according to claim 5 into the consumer goods.
   
   

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