Perfume compositions and perfumed articles and materials which contain derivatives of m-cresol as perfume component

Abstract

Perfume compositions and perfumed products characterized by a content of one or more fragrances which have a very natural leather odor and correspond to the formula ##STR1## wherein one of the two symbols R.sub.1 and R.sub.2 represents a methyl group and the other a hydrogen atom or both symbols represent a hydrogen atom and R.sub.3 represents a n-propyl, allyl, 1-propenyl-, sec.butyl, 1-buten-3-yl, isobutyl or 2-methylpropen-3-yl group.

Description

The invention relates to perfume compositions which contain derivatives of m-cresol as perfume component and to articles and materials perfumed with such derivatives or compositions containing such derivatives respectively.

There is a lasting interest in the preparation and use of synthetic perfumes because, in contrast to natural products, they can always be prepared in a quantity which is matched to the demand and with a constant quality.

Leather has a characteristic, very complex but also very valued odour. Until now a leather odour could only be approximated to by combinations of many components known per se in the perfume industry. Important components of such leather-odour compositions are birchtar oil and some substituted phenols and phenol ethers, in particular p-tert-butylphenol, p-tert-butyl-m-cresol and their methyl ethers. These compounds are characterized by a phenolic phenolic and somewhat medicinal odoriferous character. Although a phenolic note is an important aspect of the odour in the overall odour of leather, said compounds nevertheless have too little leather character to result in a really satisfactory leather odour.

It has now been found that ortho-alkyl- or alkenyl-substituted m-cresols having the formula: ##STR2## wherein one of the two groups R.sub.1 and R.sub.2 represents a methyl group and the other hydrogen, or both represent hydrogen and wherein R.sub.3 represents one of the groups n-propyl, , allyl, 1-propenyl, sec-butyl, 1-buten-3-yl, isobutyl, 2-methylpropene-3-yl, are powerful and stable fragrances with a very natural leather odour.

Various substituted phenols are known in the perfume industry, some of which have a leather-type note. Mention has already been made of p-tert-butylphenol (S. Arctander, Perfumes and Flavor Chemicals, monograph No. 504) and p-tert-butyl-m-cresol (Arctander No. 429). Arctander also mentions further p-tert-amlyphenol (No. 205), 2-tert-butyl-4,5-dimethylphenol (No. 446), 4-tert-butyl-3,5-dimethylphenol (No. 546), chavicol (No. 606), m-cresol (No. 707) and o-ethylphenol (No. 1328). Insofar as the compounds mentioned above contain an alkyl group of 3 or more C atoms, they are characterized by a 4-alk(en)ylphenol structure, with the sole exception of (no. 446) but according to Arctander this finds little or no use as a fragrance.

On the other hand, the compounds according to the invention are characterized by a 2-alk(en)yl-3-methylphenol-substituted pattern which is not found in any of the known compounds. In addition, the known compounds do indeed exhibit a somewhat phenolic leather-type note, but none of them has a complete and natural leather odour like the compounds according to the invention.

The other substituted phenols known in the perfume industry such as carvacrol (Arctander No. 573), 2,4-dimethyl-6-isopropylphenol (No. 1054), thymol (No. 2944), isothymol (No. 2945) and xylenol (No 3098), do not even exhibit any leather character at all. Said compounds mostly have medicinal and spicy odours. Thymol is, in addition, used in mandarin aroma (see Dutch patent application No. 6,403,357).

The compounds according to the invention are very suitable for use as such, or in combination with other components usual for the purpose, to impart a fine and natural leather odour to all kinds of articles and materials. The compounds may also be used with advantage in perfume compositions in which a leather note is desirable. In particular, the compounds 2-allyl-3-methylphenol, 2-allyl-3,6-dimethylphenol, 2-(prop-1-enyl)-3-methylphenol, 2-sec-butyl-3-methylphenol and 2-isobutyl-3-methylphenol excel in their fine and very long-lasting leather odour.

Here the term "perfume composition" means a mixture of fragrances and optional auxilliary substances, if required dissolved in a suitable solvent or mixed with a powdered substrate, which is used to impart a desired odour to the skin and/or all kinds of products. Examples of such products are: soaps, detergents, air fresheners, room sprays, pomanders, candles, cosmetics, such as creams, ointments, toilet waters, pre and aftershave lotions, talcum powders, hair-care products, body deodorants and antiperspirants. The compounds according to the invention are also very suitable per se for imparting a leather odour to all types of products such as leather-substitute materials.

Fragrances and mixtures of perfumes which may be used in combination with the compounds according to the invention for the preparation of perfume compositions are, for example: natural products usch as ethereal oils, absolute oils, resinoids, resins, concrete oils etc, but also synthetic fragrances such as hydrocarbons, alcohols, aldehydes, ketones, ethers, acids, esters, acetales, ketales, nitriles, etc, including saturated and unsaturated compounds, aliphatic, carbocyclic and heterocyclic compounds. Examples of fragrances which may be used in combination with the compounds according to the invention are: geraniol, geranyl acetate, linalool, linalyl acetate, tetrahydrolinalool, citronellol, citronellyl acetate, dihydromyrcenol, dihydromyrcenyl acetate, tetrahydromyrcenol, terpineol, terpinyl acetate, nopol, nopyl acetate, 2-phenylethanol, 2-phenylethyl acetate, benzyl alcohol, benzyl acetate, benzyl salicylate, styrallyl acetate, benzyl benzoate, amyl salicylate, dimethylbenzylcarbinol, trichloromethylphenylcarbinyl acetate, p-tert-butylcyclohexyl acetate, isononyl acetate, vetiveryl acetate, vetiverol, .alpha.-hexylcinnamaldehyde, 2-methyl-3-(p-tert-butylphenyl)propanal, 2-methyl-3-(p-isopropylphenyl)propanal, 3-(p-tert-butylphenyl)propanal, tricyclodecenyl acetate, tricyclodecenyl propionate, 4-(4-hydroxy-4-methylpentyl)-3-cyclohexenecarbaldehyde, 4-(4-methyl-3-pentenyl)-3-cyclohexenecarbaldehyde, 4-acetoxy3-pentyl-tetrahydropyran, 3-carboxymethyl-2-pentyl-cyclopentane, 2-n-heptylcyclopentanone, 3-methyl-2-pentyl-2-cyclopentenone, n-decanal, n-dodecanal, 9-decenol-1, phenoxyethyl isobutyrate, phenylacetaldehyde dimethylacetale, phenylacetaldehyde diethylacetale, geranyl nitrile, citronellyl nitrile, cedryl acetate, 3-isocamphylcyclohexanol, cedryl methyl ether, isolongifolanone, aubepine nitrile, aubepine, heliotropin, coumarin, eugenol, vanillin, diphenyl oxide, hydroxycitronellal, ionones, methylionones, isomethylionones, irones, cis-3-hexenol and esters thereof, indan-musks, tetralin-musks, isochroman-musks, macrocyclic ketones, macrolactone-musks, ethylene brassylate, aromatic nitro-musks.

Auxilliary materials and solvents which may be used in perfume compositions which contain compounds according to the invention are for example: ethanol, isopropanol, diethyleneglycol monoethyl ether, diethyl phthalate etc.

The quantities in which the compounds according to the invention may be used in perfume compositions or products to be perfumed may vary within wide limits, and depend, inter alia, on the nature of the product in which the perfume is used , on the nature and the quantity of the remaining components in the perfume composition and on the odour effect which is aimed at. Consequently, it is possible to specify only very rough limits which, however, provide those skilled in the art with sufficient information to be able to use the compounds according to the invention independently. In most cases a quantity of only 0.1% by weight in a perfume composition will already be sufficient to obtain a clearly perceptible odour effect. On the other hand, to achieve special odour effects, it is possible to use quantities of 90% by weight or even more in a composition. In product perfumed by means of perfume compositions these concentrations are proportionately lower depending on the quantity of composition used in the product.

The compounds according to the invention may be prepared by methods described in the literature for these and similar compounds, in particular by Claisen rearrangement of suitable phenyl alkenyl ethers which may be prepared in their turn by standard methods from m-cresol, or 3,5- or 3,6-dimethylphenol and allyl-, or butenyl or isobutenylhalide. Both the preparation of the phenyl alkenyl ethers and the Claisen rearrangement subsequent thereto are extensively described in Organic Reaction, Volume II, John Wiley & Sons, Inc., New York 1944, pages 1-48. The compounds wherein R.sub.3 is propyl, isobutyl or sec-butyl, are obtained from the corresponding unsaturated compounds by catalytic hydrogenation by standard methods, e.g. by means of 5% Pd on carbon at atmospheric or increased pressure. The compounds wherein R.sub.3 represents 1-propenyl can be obtained by alkaline isomerization of the corresponding allyl compounds, e.g. by means of 1.1 equivalent of potassium tert-butylate in dimethyl sulphoxide, for 2 hours at 70.degree. C., or as described in Organic Reactions Volume II, page 27.

If R.sub.1 =R.sup.2 =H, in the synthesis a 1:1 mixture is obtained of the desired compound according to the invention and the corresponding 6-alk(en)yl-3-methyl-phenol. These latter isomers have a phenolic odour with little leather character and are therefore not part of the invention. As already mentioned above, in many types of leather a phenolic note is an important aspect of the odour in the overall leather odour The presence of said isomers does not therefore have any disadvantageous effect on the applicability of the compounds according to the invention as leather fragrances in perfume compositions or materials to be perfumed. The isomer mixtures obtained in the synthesis may therefore be used as leather fragrances without further separation. However, it is also quite possible to separate the two isomers by means of chromatographic techniques, e.g. HPLC over silica gel modified with cyan groups so that, if required, the pure 2-alk(en)yl-3-methylphenol may nevertheless be used.

The following examples serve purely to illustrate the application of the compounds according to the invention. The invention is, however, not limited thereto.

EXAMPLE I

Preparation of 2-allyl-3-methylphenol

360 g of a 30% solution of sodium methylate in methanol were added to a mixture of 139 g of allyl chloride and 216 g of m-cresol in 15 minutes, the temperature being kept below 40.degree. C. by cooling. Stirring was then carried out at approx. 45.degree. C. or a further 4 hours, after which the reaction was terminated by pouring out the reaction-mixture into a mixture of 150 g of concentrated hydrochloric acid and 700 g of ice. 200 g of toluene were then added, stirred thoroughly and the layers were separated. The organic layer was washed neutrally with saturated sodium bicarbonate solution. After adding 4 g of solid soda, approx. 160 g of toluene were evaporated off. The remaining mixture was heated at 200.degree. C. while stirring for 4 hours, all the volatile components being distilled off. The Claisen rearrangement was terminated by allowing the mixture to cool. Fractionation was then carried out at reduced pressure.

156 g of a mixture of 2-allyl- and 6-allyl-3-methylphenol, b.p. 98.degree. C./1.1 kPa, were obtained. The mixture had a fine leather odour with a correct dose of phenolic note.

Pure 2-allyl-3-methylphenol was obtained by separating the mixture by means of HPLC via a Zorbax CN* column using a mixture of 99% pentane and 1% isopropanol as eluent. This compound had a fine odour with the typical character of fresh leather.

*Marketed by E. I. Dupont de Nemours.

EXAMPLE II

A perfume composition for a "man's cologne" was prepared according to the following recipe:

______________________________________acetylcedrene 140 parts by weightbergamot oil 130 parts by weightlemon oil 65 parts by weight.alpha.-hexylcinnamaldehyde 65 parts by weightlavandin oil 50 parts by weightmethyl dihydrojasmonate 40 parts by weightpatchouli oil 40 parts by weight5-acetyl-3-isopropyl- 30 parts by weight1,1,2,6-tetramethylindanlily of the valley, synthetic 30 parts by weightisolongifolanone 30 parts by weightaspic oil 30 parts by weightmusk ketone 20 parts by weightlabdanum resinoid 20 parts by weightylang-ylang oil 20 parts by weightmenthol 10 parts by weightmousse de chene absolute 10 parts by weightisobutylquinoline* 10 parts by weightgalbanum oil* 10 parts by weightundecylene aldehyde* 5 parts by weightmethylnonylacetaldehyde* 5 parts by weightstyrallyl acetate 5 parts by weightclove oil 5 parts by weightproduct obtained according to 30 parts by weightExample I 800 parts by weight______________________________________ *10% solution by weight in diethyleneglycol monoethyl ether.

EXAMPLE III

A perfume composition for an aftershave lotion was prepared according to the recipe below:

______________________________________cedryl acetate 230 parts by weightpatchouli oil 100 parts by weightlemon oil 100 parts by weightlavender oil 100 parts by weightbenzyl salicylate 90 parts by weightmusk ketone 53 parts by weightbergamot oil 50 parts by weightrose, synthetic 50 parts by weightcoumarin 30 parts by weightjasmin, synthetic 30 parts by weightmethyl dihydrojasmonate 30 parts by weightamber, synthetic 25 parts by weightgalbanum resinoid 20 parts by weightsandlewood oil, East Indian 20 parts by weightgeranium oil, Bourbon 20 parts by weightmousse de chene absolute 10 parts by weightbasil oil 10 parts by weightoriganum oil 2 parts by weight2-allyl-3,6-dimethylphenol 30 parts by weight 1,000 parts by weight______________________________________

EXAMPLE IV

An aftershave lotion perfumed with the composition according to Example III was prepared according to the recipe below:

A. 0.3 parts by weight of l-menthol; 0.5 parts by weight of uvinol D 50(*); 30.0 parts by weight of propyleneglycol; 535 parts by weight of ethanol. B. 2.0 parts by weight of aluminium chlorohydrate allantoate; 2.0 parts by weight of lactic acid; 400 parts by weight of water (distilled). C. 20 parts by weight of perfume (Example III); 10 parts by weight of cremophor RH40(**). The components mentioned under A., B. and C. were mixed separately to form the mixtures A., B. and C. The mixture B was then added to mixture A while stirring thoroughly. Mixture C was then added and the total mixture was homogenised by stirring. In this way, a somewhat astringent aftershave lotion was obtained, the odour of which was characterized by a pleasant leather note. (*)BASF trade mark for 2,2',4,4'-tetrahydroxybenzofuran (**)BASF trade mark for a reaction product of hydrogenated resinous oil epoxyethane.

Claims

1. A perfume composition comprising an effective odorant amount of one or more fragrancing compounds of the formula ##STR3## wherein one of the symbols R.sub.1 and R.sub.2 represents a methyl group and the other is a hydrogen atom or both symbols represent a hydrogen atom, and R.sub.3 represents an n-propyl, allyl, 1-propenyl, sec-butyl, 1-buten-3-yl, isobutyl or 2-methylpropenyl group, together with customary perfumery ingredients.

2. A perfume composition according to claim 1, comprising an effective odorant amount of one or more compounds selected from the group consisting of 2-allyl-3-methylphenol, 2-allyl-3,6-dimethylphenol, 2-(prop-1-enyl)-3-methylphenol, 2-sec-buty-3-methylphenol and 2-isobutyl-3-methylphenol.

3. A perfume composition according to claim 1, comprising at least 0.1% by weight of the fragrancing compounds given by formula (I).

4. A perfumed product comprising an effective odorant amount of one or more fragrancing compounds of the formula ##STR4## wherein one of the symbols R.sub.1 and R.sub.2 represents a methyl group and the other is a hydrogen atom or both symbols represent a hydrogen atom, and R.sub.3 represents an n-propyl, allyl, 1-propenyl, sec-butyl, 1-buten-3-yl, isobutyl or 2-methylpropenyl group.

5. A perfumed product according to claim 4, comprising an effective odorant amount of one or more compounds selected from the group consisting of 2-allyl-3-methylphenol, 2-allyl-3,6-dimethylphenol, 2-(prop-1-enyl)-3-methylphenol, 2-sec-butyl-3-methylphenol and 2-isobutyl-3-methylphenol.

6. A method of imparting a leathery note to a material comprising adding to said material an effective odorant amount of one or more compounds of the formula ##STR5## wherein one of the symbols R.sub.1 and R.sub.2 represents a methyl group and the other is hydrogen atom or both symbols represent a hydrogen atom, and R.sub.3 represents an n-propyl, allyl, 1-propenyl, sec-butyl, 1-buten-3-yl, isobutyl or 2-methylpropenyl group.

7. A method according to claim 6, wherein the compound added is selected from the group consisting of 2-allyl-3-methylphenol, 2-allyl-3,6-dimethylphenol, 2-(prop-1-enyl)-3-methylphenol, 2-sec-butyl-3-methylphenol and 2-isobutyl-3-methylphenol.