JP7269481B2 - Acetoxy fatty acid ethyl ester and fragrance composition - Google Patents

Description

The present invention relates to novel acetoxy fatty acid ethyl esters useful as perfume compounds.

In recent years, with the diversification of foods and drinks, the demand for characteristic aromas and flavors has increased, and various flavoring compounds have been demanded. In addition, with the shortage of dairy raw materials, the demand for milk-based flavors is especially increasing.

Various flavors have been proposed for the purpose of meeting this demand, including those containing 3-methylnonane-2,4-dione (Patent Document 1), and those containing specific diglycerides composed of relatively long-chain fatty acids at specific ratios. A blended mixed diglyceride is blended (Patent Document 2), and a fragrance composition is added with alkyl 5-acyloxydecanoate (excluding methyl 5-acetoxydecanoate and ethyl 5-acetoxydecanoate) (Patent Document 2). Document 3), adding ethyl 5-formyloxyalkanoate (Patent Document 4), using alkyl 5-[(1-alkoxy)ethoxy]alkanoate as an active ingredient (Patent Document 5), (E)- Addition of 6-octenal (Patent Document 6), Addition of 2,4,7-tridecatrienal (Patent Document 7), 7-dodecenoic acid, 8-dodecenoic acid, 9-dodecenoic acid or 10-dodecene Examples include those in which an acid is added (Patent Document 8). However, these were not necessarily satisfactory in terms of flavor. In addition, Patent Documents 3, 4 and 5 are proposals regarding ring-opened products of lactones, and although there are descriptions of ring-opened products of δ-lactones having 8 to 12 carbon atoms, they relate to ethyl 5-acetoxide dodecanoate. There were no suggestions. Furthermore, there has been no proposal of lactones having 13 or more carbon atoms or ring-opened products of ε-lactones.

Japanese Patent Application Laid-Open No. 2003-052330 JP 2013-153738 A Japanese Unexamined Patent Application Publication No. 2013-173708 JP 2014-031331 A JP 2015-131773 A Japanese Patent Application Laid-Open No. 2018-000022 JP 2018-057310 A JP 2019-065212 A

An object of the present invention is to provide a novel flavoring compound that can impart or enhance a milky flavor to foods and drinks, etc., and that can also be used for general purposes as a flavoring material, a method for producing the compound, and a method for producing the compound as an active ingredient. An object of the present invention is to provide a perfume composition containing the above.

The present inventors have synthesized a plurality of lactone ring-opening compounds and extensively studied their aromas. As a result, they found that a novel acetoxy fatty acid ethyl ester, which is a lactone ring-opening product with a specific carbon number, is useful as a fragrance compound. Heading The present invention has been completed.

That is, the present invention is as follows.
[1] General formula (1)

(In the formula, n is 1 or 2, and R represents an alkyl group having 4 to 9 carbon atoms.)
wherein when n is 1, R is an alkyl group having 7 to 9 carbon atoms, and when n is 2, R is an alkyl group having 4 to 6 carbon atoms.
[2] The formula according to [1], wherein when n is 1, R is an alkyl group having 7 or 9 carbon atoms, and when n is 2, R is an alkyl group having 4 or 6 carbon atoms. Acetoxy fatty acid ethyl ester.
[3] A fragrance composition containing one or more compounds selected from the acetoxy fatty acid ethyl esters described in [1] or [2] above.
[4] General formula (2)

(In the formula, n is 1 or 2, and R represents an alkyl group having 4 to 9 carbon atoms.)
When n is 1 in the formula, R is an alkyl group having 7 to 9 carbon atoms, and when n is 2 in the formula, R is an alkyl group having 4 to 6 carbon atoms, δ-lactone or ε - the lactone of general formula (3) by transesterification with ethanol using an acid catalyst

(In the formula, n is 1 or 2, and R represents an alkyl group having 4 to 9 carbon atoms.)
When n is 1 in the formula, R is an alkyl group having 7 to 9 carbon atoms, and when n is 2 in the formula, R is an alkyl group having 4 to 6 carbon atoms. and obtaining the acetoxy fatty acid ethyl ester of [1] or [2] by acylating the ethyl hydroxy fatty acid with acetic anhydride. A method for producing an ester.

The acetoxy fatty acid ethyl ester of the present invention can be used as a fragrance compound for the purpose of modulating aroma and enhancing taste. Moreover, the acetoxy fatty acid ethyl ester can be easily produced by the production method of the present invention.

The acetoxy fatty acid ethyl ester of the present invention has the general formula (1)

(In the formula, n is 1 or 2, and R represents an alkyl group having 4 to 9 carbon atoms.)
wherein when n is 1, R is an alkyl group having 7 to 9 carbon atoms, and when n is 2, R is an alkyl group having 4 to 6 carbon atoms. is.

Synthesis methods of these acetoxy fatty acid ethyl esters are not limited, but they can be synthesized, for example, by the following method.

First, represented by the general formula (2), where when n is 1, R is an alkyl group having 7 to 9 carbon atoms, and when n is 2, R is an alkyl group having 4 to 6 carbon atoms. A hydroxy fatty acid ethyl represented by the general formula (3) is obtained by transesterification with ethanol using an acid catalyst using a lactone as a substrate.

Lactones used in this reaction can be synthesized by known methods, and commercially available products can also be used.

The amount of ethanol used in this reaction is arbitrary as long as it is equivalent to or more than the lactones that are substrates, but since the transesterification reaction is a reversible reaction, it should be increased so that the equilibrium is biased toward the target product. It is preferable to use an excess amount, preferably 5 to 15 equivalents relative to the lactones that are substrates.

Any acid catalyst can be used in this reaction as long as it can be used in the transesterification reaction, and a preferred example thereof is p-toluenesulfonic acid monohydrate. The amount of the acid catalyst to be used is arbitrary as long as it is a catalytic amount, but is preferably 0.01 to 0.03 equivalents relative to the lactones as substrates.

The reaction temperature may be arbitrarily determined according to the lactones and acid catalysts used, but is preferably between 20 and 40.degree. The reaction time may be determined while monitoring the progress of the reaction by thin layer chromatography, gas chromatography, or the like, but the reaction is preferably carried out for 3 to 4 hours.

Next, the acetoxy fatty acid ethyl ester of the present invention represented by the general formula (1) is obtained by acylating the hydroxy fatty acid ethyl represented by the general formula (3) obtained by the above reaction using acetic anhydride.

The hydroxy fatty acid ethyl used in this reaction may be used after purifying the crude product obtained in the above reaction, or may be used as a crude product.

The acylating agent used in this reaction may be any carboxylic acid anhydride or carboxylic acid halide that can be used for acylation, and a preferred example thereof is acetic anhydride. The amount of the acylating agent to be used is arbitrary as long as it is equivalent to or more than the lactone substrate, but it is preferable to use an excess amount relative to the hydroxy fatty acid ethyl, preferably within the range of 2 to 3 equivalents.

Pyridine can be used as a solvent in this reaction. The amount of pyridine used can be reduced. In that case, in order to suppress the intermolecular reaction between the hydroxy fatty acid ethyl substrates, it is preferable to use a solvent that is inert to the substrate and the acylating agent. Toluene is mentioned.

Although the reaction temperature may be arbitrarily determined according to the ethyl hydroxy fatty acid and the acylating agent used, room temperature is preferred. In addition, the reaction time may be determined while monitoring the progress of the reaction by thin layer chromatography, gas chromatography, or the like, but the reaction is preferably carried out overnight.

The acetoxy fatty acid ethyl ester of the present invention obtained as described above may be purified using means such as column chromatography and vacuum distillation, if necessary.

The acetoxy fatty acid ethyl ester of the present invention can be used alone or in combination of two or more, and can also be combined with other commonly used perfume materials to form a perfume composition. The amount of the compound of the present invention when used as a fragrance composition may be arbitrarily determined in consideration of the purpose of blending and the type of fragrance composition, but is preferably 10 ppm to 10%, more preferably 100 ppm. A range of ~1% is good. In addition, the composition may be prepared by adding other additives commonly used as components other than fragrances, as long as they do not adversely affect the aroma or flavor. Furthermore, it is also possible to apply formulation techniques that are generally applied to perfumes, and it is also possible to prepare in desired forms such as powderization and encapsulation depending on the situation.

The acetoxy fatty acid ethyl ester of the present invention can be used universally as a fragrance compound. In addition, by adding it to food and drink, it is possible to impart a milky flavor with a middle to last milk fat feeling thickness and persistence at the time of eating and drinking. Furthermore, it is possible to enhance the sweetness, saltiness, and umami of food and drink, and to provide a smooth feeling, a soft, and good melting feeling in the mouth, and to impart or enhance these aromas, tastes, and textures in a well-balanced manner. Due to this, enhancement of richness is also recognized.

[Example 1] Synthesis of ethyl 5-acetoxide dodecanoate Under a nitrogen atmosphere, δ-dodecalactone (3.0 g, 15 mmol), ethanol (7.0 g), p-toluenesulfonic acid monohydrate ( 0.05 g, 0.26 mmol) was charged and stirred at 30° C. for 4 hours. Water (13 ml) was added, extraction was performed with ethyl acetate (10 mL), and the resulting ethyl acetate layer was washed twice with water (10 mL). Concentration under reduced pressure gave ethyl 5-hydroxydodecanoate (3.8 g) as a colorless oily crude product.

Under nitrogen atmosphere, ethyl 5-hydroxydodecanoate (3.8 g, 15 mmol) obtained above, toluene (10.0 g), pyridine (1.2 g), acetic anhydride (3.2 g, 31 mmol) were placed in a test tube. and stirred overnight at room temperature. Water (15.3 g) was added, extracted with toluene (10 mL), and the obtained toluene layer was washed with 5% aqueous sodium hydrogencarbonate solution (15 mL) and water (15 mL×2 times) in that order. The residue (4.7 g) obtained by concentration under reduced pressure was purified by silica gel chromatography and distillation to give ethyl 5-acetoxidedodecanoate (3.1 g, 11 mmol) as a colorless oil. Yield from δ-dodecalactone was 72%.

The physical properties of the obtained ethyl 5-acetoxide dodecanoate were as follows.
¹ H-NMR (400 MHz, CDCl ₃ ): δ ppm 0.88 (t, 3H, J = 6.9 Hz), 1.22-1.31 (m, 13H), 1.53-1.67 (m, 6H), 2.04 (s, 3H) 2.30 (t, 2H, J = 7.3 Hz), 4.13 (q, 2H, J = 7.2 Hz), 4.87 (quin, 1H, J = 6.0 Hz)
¹³ C-NMR (400 MHz, CDCl ₃ ): δppm 13.99, 14.15, 20.63, 21.15, 22.55, 25.20, 29.09, 29.10, 29.37, 31. 69, 33.31, 33.92, 60.19, 73.70, 170.78, 173.28

[Example 2] Synthesis of ethyl 5-acetoxytetradecanoate Under a nitrogen atmosphere, δ-tetradecalactone (1.5 g, 6.6 mmol), ethanol (3.0 g), p-toluenesulfonic acid monohydrate were added to a test tube. A hydrochloride (0.02 g, 0.11 mmol) was charged and stirred at 30° C. for 3 hours. Water (12 ml) was added, extraction was performed with toluene (10 mL), and the obtained toluene layer was washed twice with water (10 mL). Concentration under reduced pressure gave ethyl 5-hydroxytetradecanoate (1.8 g) as a colorless oily crude product.

Under nitrogen atmosphere, ethyl 5-hydroxytetradecanoate (1.8 g, 6.6 mmol) obtained above, toluene (10.0 g), pyridine (0.2 g), acetic anhydride (2.0 g, 19.6 mmol) was charged and stirred overnight at room temperature. Water (10 ml) was added, extraction was performed with toluene (10 mL), and the obtained toluene layer was washed successively with 5% aqueous sodium hydrogencarbonate solution (10 mL) and water (10 mL×2 times). The residue (1.9 g) obtained by concentration under reduced pressure was purified by silica gel chromatography and distillation to give ethyl 5-acetoxytetradecanoate (0.7 g, 2.2 mmol) as a colorless oil. . Yield from δ-tetradecalactone was 33%.

The physical properties of the obtained ethyl 5-acetoxytetradecanoate were as follows.
¹ H-NMR (400 MHz, CDCl ₃ ): δ ppm 0.88 (t, 3H, J = 6.4 Hz), 1.23-1.27 (m, 17H), 1.52-1.67 (m, 6H), 2.04 (s, 3H) 2.30 (t, 2H, J = 7.3 Hz), 4.13 (q, 2H, J = 7.5 Hz), 4.87 (quin, 1H, J = 5.9Hz)
¹³ C-NMR (400 MHz, CDCl ₃ ): δ ppm 14.02, 14.16, 20.63, 21.16, 22.60, 25.21, 29.21, 29.42, 29.43, 29. 44, 31.81, 33.31, 33.92, 33.94, 60.19, 73.70, 170.78, 173.28

[Example 3] Synthesis of ethyl 6-acetoxydecanoate Under a nitrogen atmosphere, ε-decalactone (1.9 g, 11 mmol), ethanol (4.0 g), p-toluenesulfonic acid monohydrate (0 .03 g, 0.16 mmol) was charged and stirred at 30° C. for 4 hours. Water (10 ml) was added, extraction was performed with toluene (10 mL), and the obtained toluene layer was washed twice with water (10 mL). Concentration under reduced pressure gave ethyl 6-hydroxydecanoate (2.8 g) as a colorless oily crude product.

In a nitrogen atmosphere, ethyl 6-hydroxydecanoate (2.8 g, 11 mmol) obtained above, toluene (10.0 g), pyridine (1.0 g), acetic anhydride (2.4 g, 24 mmol) were placed in a test tube. was added and stirred overnight at room temperature. Water (12.2 g) was added, extracted with toluene (10 mL), and the obtained toluene layer was washed with 5% aqueous sodium hydrogencarbonate solution (14 mL) and water (13 mL×3 times) in that order. The residue (2.9 g) obtained by concentration under reduced pressure was purified by silica gel chromatography and distillation to give ethyl 6-acetoxydecanoate (2.6 g, 10 mmol) as a colorless oil. The yield from ε-decalactone was 88%.

The physical properties of the obtained ethyl 6-acetoxydecanoate were as follows.
¹ H-NMR (400 MHz, CDCl ₃ ): δ ppm 0.89 (t, 3H, J = 6.9 Hz), 1.22-1.38 (m, 9H), 1.49-1.67 (m, 6H), 2.04 (s, 3H), 2.29 (t, 2H, J = 7.4 Hz), 4.12 (q, 2H, J = 7.0 Hz), 4.86 (quin, 1H, J=6.2Hz)
¹³ C-NMR (400 MHz, CDCl ₃ ): δ ppm 13.90, 14.16, 21.17, 22.51, 24.77, 24.79, 27.39, 33.68, 33.71, 34. 12, 60.13, 74.00, 170.82, 173.49

[Example 4] Synthesis of ethyl 6-acetoxide dodecanoate Under a nitrogen atmosphere, ε-dodecalactone (2.0 g, 10 mmol), ethanol (6.0 g), p-toluenesulfonic acid monohydrate ( 0.05 g, 0.26 mmol) was charged and stirred at 30° C. for 4 hours. Water (10 ml) was added, extraction was performed with ethyl acetate (10 mL), and the resulting ethyl acetate layer was washed twice with water (10 mL). Concentration under reduced pressure gave ethyl 6-hydroxydodecanoate (3.1 g) as a colorless oily crude product.

Under nitrogen atmosphere, ethyl 6-hydroxydodecanoate (3.1 g, 10 mmol) obtained above, toluene (8.0 g), pyridine (0.8 g), acetic anhydride (2.3 g, 23 mmol) were placed in a test tube. was added and stirred overnight at room temperature. Water (15.8 g) was added, extraction was performed with toluene (10 mL), and the obtained toluene layer was washed with 5% aqueous sodium hydrogencarbonate solution (15 mL) and water (15 mL×2 times) in that order. The residue (2.7 g) obtained by concentration under reduced pressure was purified by silica gel chromatography and distillation to give ethyl 6-acetoxidedodecanoate (2.3 g, 8 mmol) as a colorless oil. The yield from ε-dodecalactone was 81%.

The physical properties of the obtained ethyl 6-acetoxide dodecanoate were as follows.
¹ H-NMR (400 MHz, CDCl ₃ ): δ ppm 0.88 (t, 3H, J = 6.9 Hz), 1.23-1.38 (m, 13H), 1.50-1.67 (m, 6H), 2.03 (s, 3H) 2.29 (t, 2H, J = 7.4 Hz), 4.12 (q, 2H, J = 7.2 Hz), 4.86 (quin, 1H, J = 6.3Hz)
¹³ C-NMR (400 MHz, CDCl ₃ ): δ ppm 13.86, 14.05, 21.02, 22.40, 24.66, 24.69, 25.08, 29.00, 31.56, 33. 60, 33.93, 34.00, 59.99, 73.87, 170.64, 173.32

[Example 5] Aroma Evaluation of Acetoxy Fatty Acid Ethyl Ester of the Present Invention The compounds of the present invention obtained in Examples 1 to 4 were evaluated by four well-trained panelists. Aroma evaluation was carried out by preparing each compound in a sample bottle, using the aroma of the mouth of the bottle and odor paper impregnated with the compound. Table 1 shows the average fragrance evaluation by 4 persons.

[Example 6] Evaluation of coffee milk to which the compound of the present invention has been added A sensory evaluation was performed. The sensory evaluation was performed by 4 well-trained panelists according to the 7-level evaluation shown in Table 2. Table 3 shows the results. As a result of the sensory evaluation, all the compounds of the present invention were found to have the effect of imparting a thick milk fat feeling from the middle to the last and a persistent milk flavor. In addition, enhancement of sweetness was also observed. Furthermore, it gave smoothness, softness, and a good melt-in-the-mouth feeling in the oral cavity, and it also became smooth when going down the throat. By imparting or enhancing these aroma, taste, and texture in a well-balanced manner, enhanced richness was also recognized.

[Example 7] Evaluation of cookies to which butter flavor containing the compound of the present invention was added The butter flavor shown in Table 4 to which 1% of the compound of the present invention shown in Table 1 was added was added to the cookie dough shown in Table 5. The cookie dough was placed in an oven preheated to 150° C. at the bottom and 180° C. at the top and baked for 7 minutes to prepare cookies. Table 6 shows the results. As a result of the sensory evaluation, all the compounds of the present invention were found to have the effect of imparting a thick milk fat feeling from the middle to the last and a persistent milk flavor. As a result, the prominent lactone flavor was suppressed, resulting in a harmonious buttery flavor. In addition, enhancement of sweetness, saltiness and umami was also observed. Furthermore, it gave smoothness, softness, and a good melt-in-the-mouth feeling in the oral cavity, and it also became smooth when going down the throat. By imparting or enhancing these aroma, taste, and texture in a well-balanced manner, enhanced richness was also recognized.

Claims (3)

General formula (1)

(In the formula, n is 1 or 2, and R represents an alkyl group having 4 to 9 carbon atoms.)
wherein when n is 1, R is an alkyl group having 7 to 9 carbon atoms, and when n is 2, R is an alkyl group having 4 to 6 carbon atoms. 2. The acetoxy fatty acid ethyl according to claim 1, wherein when n in the formula is 1, R is an alkyl group with 7 or 9 carbon atoms, and when n is 2 in the formula, R is an alkyl group with 4 or 6 carbon atoms. ester. general formula (2)

(In the formula, n is 1 or 2, and R represents an alkyl group having 4 to 9 carbon atoms.)
When n is 1 in the formula, R is an alkyl group having 7 to 9 carbon atoms, and when n is 2 in the formula, R is an alkyl group having 4 to 6 carbon atoms or δ-lactone or ε - the lactone of general formula (3) by transesterification with ethanol using an acid catalyst

(In the formula, n is 1 or 2, and R represents an alkyl group having 4 to 9 carbon atoms.)
When n is 1 in the formula, R is an alkyl group having 7 to 9 carbon atoms, and when n is 2 in the formula, R is an alkyl group having 4 to 6 carbon atoms. and obtaining the acetoxy fatty acid ethyl ester according to claim 1 or 2 by acylation of said hydroxy fatty acid ethyl with acetic anhydride. .