EP0694605B1 - Cyclic diester and its use as perfuming ingredient - Google Patents

Description

The present invention relates to the field of perfumery. It concerns, in in particular, the use in perfumery of diethyl 1,4-cyclohexanedicarboxylate.

dans laquelle R₁ et R₂ sont des résidus d'hydrocarbures aliphatiques ou alicycliques et avec un nombre d'atomes de carbone de 13 au moins, à l'exception du cas dans lequel R₁ et R₂ représentent les deux un radical méthyle.The chemical structure of this compound is known from the prior art. Furthermore, document JP A 52 136927 also discloses the use in perfumery of 1,2 and 1,3-dicarboxylates of general formula

in which R ₁ and R ₂ are residues of aliphatic or alicyclic hydrocarbons and with a number of carbon atoms of at least 13, with the exception of the case in which R ₁ and R _{2 both} represent a methyl radical.

These compounds are described as having a green, sweet odor of the type apple, their usefulness not being as perfuming ingredients but rather as "harmonizing" or "modulating" agents of odors, the function of which is to soften the odor of the basic perfuming ingredients in a given composition, without however change the olfactory character of the latter.

This document is completely silent regarding 1,4-dicarboxylates of similar structure, and to our knowledge there is in art no description, or even suggestion, of the possible usefulness of 1,4-dicarboxylates, and in particular 1,4-cyclohexanedicarboxylate and diethyl, in perfumery.

It is therefore surprisingly that we have now discovered that the Diethyl 1,4-cyclohexanedicarboxylate indeed has a rare combination of fragrant flowery, fruity type, namely a flowery odor and whose character fruity evokes the smells of strawberry and pear, very ethereal, with a slight pineapple side background. It's a very natural fruit smell and not at all candied-lactonic, also endowed with remarkable tenacity for this type of odor.

However, it turns out that perfumery has a real lack of light fruity notes, ethereal and also tenacious. Among the known compounds having these characteristics, it would appear that only Fructone® (2-methyl-1,3-dioxolane-2-acetate ethyl; origin: International Flavors and Fragrances) has a certain tenacity. On the other hand, the only known fruity and tenacious notes at the same time are very food, evoking candied fruit and fruit compote more than the fruity note ethereal released by a fresh fruit. This is particularly the case for fruity lactones, ethyl methyl phenyl glycidate, raspberry ketone. The ethereal fruity notes known in the prior art are very volatile esters such as, for example, acetate hexyl, heptyl, octyl, allyl and ethyl caproate and ethyl butyrate. Unlike the latter, diethyl 1,4-cyclohexanedicarboxylate appears to be very stubborn, as well on wet as on textiles, as shown in the examples presented later.

By its structure, diethyl 1,4-cyclohexanedicarboxylate can be present in two stereoisomeric forms, which have odorous properties distinct from each other, and again from those of their mixtures. Thus, cis-1,4-cyclohexanedicarboxylate of diethyl has a more powerful and persistent odor than that of its trans configuration isomer, with a lot of volume, and in which the odorous characteristics typical of the mixture of isomers are best represented cited above. In general, both the two isomers and their mixtures are useful fragrance ingredients.

The cis configuration isomer and mixtures containing a quantity preponderant of this isomer are however preferred perfume ingredients according to the invention.

Diethyl 1,4-cyclohexanedicarboxylate and its configuration isomers cis or trans, can be used in fine perfumery as well as perfumery functional. They are suitable for the preparation of various perfume compositions, perfume bases and concentrates, as well as perfumes and eau de toilette, to which they impart very natural fruity characters. Their application in perfume various items such as soaps, shower or bath gels, shampoos, creams or lotions conditioner, cosmetic preparations or body or air fresheners is also advantageous.

Furthermore, they are also suitable for perfuming detergents or fabric softeners, their fragrant notes being of an excellent tenacity, and of products maintenance.

The proportions in which the compounds according to the invention can be incorporated in the aforementioned miscellaneous products vary in a range of values very extensive. These values are dependent on the nature of the product to be perfumed and the desired olfactory effect, as well as the nature of the co-ingredients in a composition given, when the compounds of the invention are used in admixture with perfuming co-ingredients, solvents or adjuvants customary in the art. Of course, the compounds according to the invention can also be added to the compositions and scented articles either alone or in solution in commonly used solvents.

By way of example, mention may be made of concentrations of the order of 1 to 5%, or even 10% or more by weight of compound of the invention, relative to the weight of composition fragrance in which it is incorporated. Concentrations much lower than these can be used when these compounds are applied in the perfume of various products mentioned above.

Diethyl 1,4-cyclohexanedicarboxylate and its isomers are either available on the market, either they can be easily prepared from products available on the market and using conventional reactions.

This is an additional advantage of their use according to the invention, insofar as they constitute original perfume ingredients and economically interesting, their synthesis on an industrial scale being easy and good market.

There are many methods for their preparation. For example acid 1,4-cyclohexanedicarboxylic being a commercially available compound (from Aldrich, for example), diethyl 1,4-cyclohexanedicarboxylate can be prepared by simple esterification of this acid, using the appropriate alcohol and in the presence of an acid protonic or an acidic resin. This is a perfectly classic reaction, including the conditions are capable of being optimized by a person skilled in the art without others details are required here.

Alternatively, this compound can be prepared from the corresponding dimethylated diester derived from benzene, which is commercially available (BASF or HÜLS), using conventional reactions illustrated in the following scheme:

The reactions illustrated in this diagram are carried out under conditions conventional, described in detail below. The desired ester is obtained in the form of a mixture of cis and trans configuration isomers. Where appropriate, these isomers can then be separated from said mixture by crystallization from suitable solvents, in which only one of the isomers is soluble.

I.

A. HydrogénationUne solution du phényl-diméthylcarboxylate approprié (Fluka, 100 g, 0,51 mole) et de Rh/C à 5% (2 g, Engelhard) dans le méthanol (50 ml) a été hydrogénée dans un autoclave, à une température de 160°C et une pression de 2x10⁷ Pa d'hydrogène. Après filtration et concentration, le produit brut a été distillé (95°C/30 Pa) pour fournir le 1,4-cyclohexanedicarboxylate de diméthyle correspondant avec un rendement de pratiquement 100%.

B. SaponificationUne solution du dicarboxylate préparé selon A. (25 g, 0,125 mole), NaOH (11 g, 0,275 mole) dans l'eau (300 ml) a été portée à reflux pendant 5 h et ensuite refroidie et acidifiée. On a filtré le précipité et lavé à l'eau pour obtenir, après séchage, l'acide 1,4-cyclohexanedicarboxylique correspondant au diester de départ sous forme d'un mélange d'isomères cis/trans.

C. EstérificationUne solution de l'acide préparé sous B. (5 g, 29 mmole), H₂SO₄ conc. (2 ml) et d'éthanol (50 ml), a été portée à reflux pendant 5 h et ensuite concentrée. On a dilué à l'éther, lavé avec NaOH à 5% et saumure. Le produit à été distillé au four à boules pour fournir le 1,4-cyclohexanedicarboxylate de diéthyle.Le produit de la réaction a été ensuite soumis à une chromatographie préparative en phase gazeuse (3,5 m Carbowax 15%, He 30 m/min) pour fournir le 1,4-cyclohexanedicarboxylate de diéthyle et le 1,4-cyclohexane dicarboxylate de méthyle éthyle.
1,4-cyclohexanedicarboxylate de diéthyle:
Rapport cis/trans : 15:4
Pureté : 99%
P. Eb. : 90°C/10 Pa

RMN(¹³C):

isomère cis : 40,8(d); 26,1(t); 26,1(t); 40,8(d); 26,1(t);
26,1(t) δppm
isomère trans : 42,6(d); 28,1(t); 28,1(t); 42,6(d); 28,1(t);
28,1(t) δppm

1,4-cyclohexanedicarboxylate de méthyle éthyle:
Rapport cis/trans : 3:1
Pureté : 98%
P. Eb. : 90°C/10 Pa

RMN(¹³C) :

isomère cis : 40,7(d) ; 26(t) ; 26(t) ; 40,7(d) ; 26(t) ;
26(t) δppm
isomère trans : 42,4(d); 28,1(t); 28,1(t); 42,5(d) ; 28,1(t);
28,1(t) δppm

Odeur : fleurie, fruitée.

II. trans-1,4-cyclohexanedicarboxylate de diméthyle et cis-1,4-cyclohexane dicarboxylate de diméthyleOn a filtré le 1,4-cyclohexanedicarboxylate de diméthyle (provenance: Hüls ; rapport cis/trans 2:1; produit mi-solide/mi-liquide) pour séparer les eaux-mères des cristaux. On a pris ces derniers (14,5 g) dans un mélange de 45 ml d'éther de pétrole 30-50° et 7 ml de tert-butyl méthyl éther et cristallisé à chaud. Les cristaux ainsi obtenus (9,2 g) contenaient le trans-1,4-cyclohexanedicarboxylate de diméthyle (pureté : 98%) ayant les caractères analytiques suivants :
P. f. : 68,1°C
RMN(¹H, 360MHz) : 3,67(s, 6H) ; 2,28(m, 2H) ; 2,05(m, 4H) ; 1,45(m, 4H) δppm
RMN(¹³C, 90MHz) : 175,9(2s) ; 51,6(2q) ; 42,4(2d) ; 28,1(4t) δppm
SM: 169(11), 168(30), 141(35), 140(94), 109(32), 108(46), 82(10), 81(100), 80(25), 79(22), 67(15), 59(20), 55(10)On a ajouté aux eaux-mères obtenues après filtration susmentionnée (92,0 g) 22 ml d'éther de pétrole 30-50° et placé le tout au congélateur. On a ainsi obtenu des cristaux (72,9g) qui ont été distillés sur colonne Vigreux de 15 cm (108°C/3x10²Pa) pour fournir 37,08 g de cis-1,4-cyclohexanedicarboxylate de diméthyle (pureté : 96% ; mélange cis/trans 75:25) ayant les caractères analytiques suivants :
RMN(¹H, 360MHz) : 3,68(s, 6H) ; 2,48(m, 2H) ; 1,90(m, 4H) ; 1,68(m, 4H) δppm
RMN(¹³C, 90MHz) : 175,4(2s) ; 51,6(2q) ; 40,7(2d) ; 26,1(4t) δppmOdeur : fruitée, rappelant l'odeur de pomme cuite.

Alternatively, the cis and trans isomers of this diester can be obtained by esterification of the cis and trans isomers of 1,4-cyclohexanedicarboxylic acid. The cis and trans isomers of this acid are also commercially available.
Diethyl 1,4-cyclohexanedicarboxylate was prepared as follows:

I.

A. Hydrogenation A solution of the appropriate phenyl dimethylcarboxylate (Fluka, 100 g, 0.51 mole) and 5% Rh / C (2 g, Engelhard) in methanol (50 ml) was hydrogenated in an autoclave, at a temperature 160 ° C and a pressure of 2x10 ⁷ Pa of hydrogen. After filtration and concentration, the crude product was distilled (95 ° C / 30 Pa) to provide the corresponding dimethyl 1,4-cyclohexanedicarboxylate with a yield of almost 100%.

B. Saponification A solution of the dicarboxylate prepared according to A. (25 g, 0.125 mole), NaOH (11 g, 0.275 mole) in water (300 ml) was brought to reflux for 5 h and then cooled and acidified. The precipitate was filtered and washed with water to obtain, after drying, 1,4-cyclohexanedicarboxylic acid corresponding to the starting diester in the form of a mixture of cis / trans isomers.

C. Esterification A solution of the acid prepared under B. (5 g, 29 mmol), H ₂ SO ₄ conc. (2 ml) and ethanol (50 ml), was brought to reflux for 5 h and then concentrated. Diluted with ether, washed with 5% NaOH and brine. The product was distilled in a ball oven to provide diethyl 1,4-cyclohexanedicarboxylate. The reaction product was then subjected to preparative gas chromatography (3.5 m Carbowax 15%, He 30 m / min ) to provide the diethyl 1,4-cyclohexanedicarboxylate and the ethyl methyl 1,4-cyclohexane dicarboxylate.
Diethyl 1,4-cyclohexanedicarboxylate :
Cis / trans ratio: 15: 4
Purity: 99%
P. Eb. : 90 ° C / 10 Pa

NMR ( ¹³ C):

cis isomer: 40.8 (d); 26.1 (t); 26.1 (t); 40.8 (d); 26.1 (t);
26.1 (t) δppm
trans isomer: 42.6 (d); 28.1 (t); 28.1 (t); 42.6 (d); 28.1 (t);
28.1 (t) δppm

Ethyl methyl 1,4-cyclohexanedicarboxylate :
Cis / trans ratio: 3: 1
Purity: 98%
P. Eb. : 90 ° C / 10 Pa

NMR ( ¹³ C):

cis isomer: 40.7 (d); 26 (t); 26 (t); 40.7 (d); 26 (t);
26 (t) δppm
trans isomer: 42.4 (d); 28.1 (t); 28.1 (t); 42.5 (d); 28.1 (t);
28.1 (t) δppm

Odor: flowery, fruity.

II . dimethyl trans-1,4-cyclohexanedicarboxylate and dimethyl cis-1,4-cyclohexane dicarboxylate Dimethyl 1,4-cyclohexanedicarboxylate was filtered (source: Hüls; cis / trans ratio 2: 1; semi-solid / mi product -liquid) to separate the mother liquors from the crystals. These were taken (14.5 g) in a mixture of 45 ml of petroleum ether 30-50 ° and 7 ml of tert-butyl methyl ether and hot crystallized. The crystals thus obtained (9.2 g) contained dimethyl trans-1,4-cyclohexanedicarboxylate (purity: 98%) having the following analytical characteristics:
P. f. : 68.1 ° C
NMR ⁽¹ H, 360MHz): 3.67 (s, 6H); 2.28 (m, 2H); 2.05 (m, 4H); 1.45 (m, 4H) δppm
NMR ( ¹³ C, 90MHz): 175.9 (2s); 51.6 (2q); 42.4 (2d); 28.1 (4t) δppm
SM: 169 (11), 168 (30), 141 (35), 140 (94), 109 (32), 108 (46), 82 (10), 81 (100), 80 (25), 79 (22 ), 67 (15), 59 (20), 55 (10) 22 ml of petroleum ether 30-50 ° were added to the mother liquors obtained after filtration mentioned above (92.0 g) and placed in the freezer. . Crystals (72.9 g) were thus obtained which were distilled on a 15 cm Vigreux column (108 ° C / 3 × 10 ² Pa) to provide 37.08 g of dimethyl cis-1,4-cyclohexanedicarboxylate (purity: 96 %; cis / trans mixture 75:25) having the following analytical characteristics:
NMR ⁽¹ H, 360MHz): 3.68 (s, 6H); 2.48 (m, 2H); 1.90 (m, 4H); 1.68 (m, 4H) δppm
NMR ( ¹³ C, 90MHz): 175.4 (2s); 51.6 (2q); 40.7 (2d); 26.1 (4t) δppmOdeur: fruity, reminiscent of the smell of baked apple.

diethyl cis-1,4-cyclohexanedicarboxylate and trans-1,4-cyclohexane diethyl dicarboxylate

These two compounds can be obtained by transesterification, under mild conditions [see, for example, R. Imwinkelried et al., Org. Synth. 65 , 230 (1987)], dimethyl cis- and trans-1,4-cyclohexanedicarboxylate.
Alternatively, they can be prepared from cis- and trans-1,4-cyclohexanedicarboxylic acids, which are commercially available (Aldrich and Bader, for example) or can be easily prepared from the above-mentioned dimethyl dicarboxylates (saponification with NaOH in ethanol).
According to this last method, we proceeded as follows:

cis configuration isomer

4.15 g of cis-1,4-cyclohexanedicarboxylic acid (87% purity; cis / trans 93: 7) were loaded into a flask with water separator, 3.35 g of ethanol, 3.71 g of 'isopropyl ether and 0.10 g of p-toluenesulfonic acid, and heated to reflux. After approximately 9 h of reaction, the mixture was poured into a decanter and washed with 10 ml of saturated NaHCO ₃ solution, twice with 10 ml of H ₂ O and once with 5 ml of saturated NaCl solution. After drying over Na ₂ SO ₄ , filtration and concentration, distillation was carried out on an 8 cm Vigreux column to obtain a liquid product having the following characteristics:
Purity: 93%
B.p .: 110 ° C / 1.5x10 ² Pa
NMR ⁽¹ H, 360MHz): 4.14 (q, J = 8Hz, 4H); 2.45 (m, 2H); 1.90 (m, 4H); 1.68 (m, 4H); 1.26 (t, J = 8Hz, 6H) δppm
NMR ( ¹³ C, 90MHz): 175.0 (2s); 60.2 (2t); 40.8 (2t); 20.1 (4t); 14.3 (2q) δppm
SM: 228 (M ⁺ , 1), 183 (29), 182 (16), 155 (29), 154 (79), 109 (48), 108 (72), 82 (10), 81 (100), 80 (42), 79 (20), 67 (20), 29 (9)

trans configuration isomer

Prepared analogously to the preceding compound, but from trams-1,4-cyclohexanedicarboxylic acid (98% pure). A crystalline solid is obtained which can be recrystallized hot from petroleum ether 30-50 °.
P. f. : 43.4 ° C
Purity: 94%
NMR ⁽¹ H, 360MHz): 4.30 (q, J = 8Hz, 4H); 2.26 (m, 2H); 2.05 (m, 4H); 1.46 (m, 4H); 1.25 (t, J = 8Hz, 6H) δppm
NMR ( ¹³ C, 90MHz): 175.5 (2s); 60.2 (2t); 42.6 (2d); 28.1 (4t); 14.2 (2q) δppm
SM: 228 (M ⁺ , 1), 183 (8), 182 (21), 155 (52), 154 (100), 109 (41), 108 (39), 81 (80), 79 (20), 78 (14), 67 (12)

The invention will now be described in more detail using the following examples:

Example 1 Perfuming composition

A basic perfume composition was prepared by mixing the following ingredients: Ingredients Parts by weight Essence of synthetic amber 100 Bergamot essence 100 Iralia® 100 Musk ketone 80 50% absolute oak moss 250 Crystal foam 50 Essence of patchouli 70 Orange essence 40 Bourbon vetyver essence 80 Wardia® 80 Total 950

To this basic Cyprus-type composition, 50 parts by weight of diethyl 1,4-cyclohexanedicarboxylate were added to obtain a new composition A, 50 parts by weight of Fructone® to obtain composition B and 50 parts by weight of undecalactone to obtain a composition C. The latter then developed a chypre-like odor recalling the fragrance of the Femme® perfume by Rochas. It had a very powerful and dominant lactonic note, with a nutritional character.
Composition B had a fruity, elegant odor but whose fruity character disappeared completely after 3 hours from the smell of a wet cloth soaked in this composition.
The new composition A had an even more elegant odor than that of composition B and less fruity-food than that of composition C. In addition, its fruity, strawberry, pear character persisted throughout the day. These effects were even more accentuated when the diethyl 1,4-cyclohexanedicarboxylate was replaced by its isomer of cis configuration in the pure state.

Example 2 Perfuming composition

A basic perfume composition was prepared using the following ingredients: Ingredients Parts by weight Benzyl acetate 75 Phenylethyl acetate 75 Bergamot essence 50 Citronellol 185 Geraniol 200 Linalol 60 Essence of patchouli 25 Phenethylol 260 Absolute rose 20 Bulgarian rose essence 10 Total 960

To this basic composition of the white rose type, 40 parts have been added. weight of diethyl 1,4-cyclohexanedicarboxylate (composition A) and 40 parts by weight of Fructone® (composition B). The new composition A thus obtained then developed a much more natural, fruity-ethereal odor than that of composition B, the latter having a more binding odor wine, alcoholic and fermented. Furthermore, while the fruity note of the composition B completely faded within 3 hours, the composition A had retained its fruity-ethereal character throughout the day.

Example 3 Substance substantivity test

Perfumed detergent samples were prepared from an unscented detergent powder, to which were added 0.1% by weight of diethyl 1,4-cyclohexanedicarboxylate (sample A), Fructone® (sample B), respectively , hexyl acetate (sample C) and allyl caproate (sample D).
With these four samples, batches of standard textiles were washed in four washing machines. The four batches of textiles were then evaluated blindly on leaving the machine and after drying, by a panel of expert perfumers, who had to judge the intensity of the fruity note exhaled over time, by assigning a value included in an increasing scale from 0 to 10.
The results of this blind assessment are summarized in the following table: Wash sample Textiles leaving the machine Textiles after 0.5 h 1 hr 1.5 hrs 2 hrs 3 hrs 4 hrs 6 a.m. 8 a.m. AT 8 7 6 5 4 4 4 2 1 B 6 5 4 3 2 2 1 0 - VS 10 5 0 - - - - - - D 9 5 2 0 - - - - -

The results of these tests show that only textiles washed with sample A, containing the compound according to the invention, develop still a fruity odor after 4 h, odor that lasts a few more hours, when all the other textiles no longer smell.

Claims (5)

1. A perfuming composition or a perfumed article containing as a perfuming ingredient diethyl 1,4-cyclohexanedicarboxylate.
2. The perfuming composition or perfumed article according to claim 1, characterised in that diethyl 1,4-cyclohexanedicarboxylate is present in the form of its cis isomer or of a mixture containing a predominant amount of the cis isomer.
3. A perfume or cologne, a soap, a bath or shower gel, a shampoo, a cream or hair conditioner, a cosmetic preparation, a body deodorant or an air freshener, a detergent, a fabric softener or a household product, which contains as a perfuming ingredient diethyl 1,4-cyclohexanedicarboxylate.
4. Use of diethyl 1,4-cyclohexanedicarboxylate as a perfuming ingredient.
5. Use according to claim 4, characterised in that diethyl 1,4-cyclohexanedicarboxylate is present in the form of its cis isomer or of a mixture containing a predominant amount of the cis isomer.