CH637612A5 - Substituted cyclohexanes - Google Patents

Description

The invention relates to new a-hydroxyethyl-4-t-alkylcy-clohexanes which have sandalwood notes and can be used as fragrances; the invention also relates to fragrance compositions containing such compounds.

Like many other well-known natural substances that have extremely valuable fragrance properties, the East Indian sandalwood oil is exposed to the randomness of the natural substances. Perfumers oppose the widespread use of this material by the fact that it is only available to a limited extent and at a high price.

There has been no shortage of attempts to replace sandalwood oil with synthetic substitutes. Although it is known that a- and ß-Santalol are the components of sandalwood oil that are responsible for the desired fragrance properties, these two alcohols have so far not been accessible by any commercially attractive process. It is therefore logical that any substance that has sandalwood oil properties and that is accessible in an economical way will immediately draw the attention of the perfumers who are interested in sandalwood oil substitutes.

The present invention now relates to new a-hydroxy-ethyl-4-t-alkylcyclohexanes of the formula

10th

15 wherein Rj is a tert. C6- or C7-alkyl radical, the tert. C atom is attached to the cyclohexane ring.

The tert. In the context of the present invention, alkyl radical is both aliphatic tert. Alkyl groups as well as ali-cyclic tert. Include alkyl groups.

20 The new compounds of the present invention are accessible in various ways.

According to the invention, the new compounds are obtained by having a compound of the formulas or or in which Rj has the above meaning

hydrated.

The new compounds and the starting materials required in the preparation of these compounds can be obtained from the corresponding t-alkylbenzenes or 4-t-alkylcyclohexanes in various ways, as is shown graphically below. The intermediates listed in the reaction scheme are commercially available or can be prepared by methods known per se. In the process according to the invention, compounds IIa, IIb or Ile always serve as starting materials.

HC = C

rune

A / * /

637 612

Priedel Crafts

CH- '°

CA]

Kondakov

CH- -0

?

Darzens [d]

ÎV * /

■ * 3 * //

R. =

R

2 Me jT o-, TTb, TJo

IIb t-alkyl as defined above H, CH5 Li, Na, K

0> tftndu * ßp ~

/ YyiaJ ^ <d /, e * 1

According to reaction route A, a t-alkylbenzene according to Frie-del Crafts can be acetylated, a reaction mixture being obtained which essentially consists of 4-t-alkyl acetyl benzene IIa. This ketone can then be hydrogenated to the desired alcohol I using a suitable catalyst.

According to reaction path B, the 4-t-alkylcyclo-hexanone is reacted with a suitable acetylide, HCsCMe [Me = Li, Na or K] to give the corresponding ethynyl alcohol, which is then converted into the corresponding acetylcyclohexene by the known rupre rearrangement (ie under the influence of formic acid) Ile is convicted. This 4-t-alkyl-1-acetylcyclohexene can then be hydrogenated to the desired alcohol I in a one- or two-stage process.

According to reaction route C, the 4-t-alkylcyclo-hexanone is converted into the 4-t-alkylcyclohexene by first reducing and then dehydrating. The olefin obtained can then be converted 55 using the known Kondakov reaction into a reaction mixture which contains the 4-t-alkyl-1-acetylcyclohexene ile; As mentioned above, this cyclohexene can be converted into the desired alcohol I.

According to route D, a 4-t-allylcyclohexanone is converted into the aldehyde Ild 60 (R2 = H) if esters of chloroacetic acid are used, or into the ketone Ild (R2 = CH) if esters of a - Chloropropionic acid can be used. The ketones obtained can be converted into the corresponding alcohols I by reducing the carbonyl group (i.e. using reducing agents which can reduce 65 ketones to alcohols). The aldehydes produced by the Darzen's reaction can be converted to alcohols I by reacting with an appropriate, i.e. egg

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organometallic derivative which gives off the CH3 residue, such as a methyl lithium reagent or a Grignardre agent, for example CH3Li, CH3MgCl, CH3MgBr, CH3MgJ.

As mentioned above, the alcohols of the present invention are accessible in various ways. Many of the l-acetyl-4-t-alkylbenzenes, l-acetyl-4-t-alkylcyclohexenes, l-acetyl-4-t-alkylcyclohexanes and 4-t-alkyl-cyclohexylcarboxaldehydes (l-formyl-4- t-alkylcyclo-hexanes) which are used as intermediates are known or can be prepared by methods known per se, for example as shown in the reaction scheme. For example, the l-acetyl-4-t-butyl cyclohexene from M.S. Newman et al., J. Am. Chem. Soc. 82: 4098 (1960); 1-Formyl-4-t-butylcyclohexane is described by B. Cross et al., J. Chem. Soc., 3895 (1960), and finally 4-t-butylacetophenone is described by J.C. Butler et al., J. Am. Chem. Soc., 76, 1906 (1954).

According to method A, the 1-acetyl-4-t-alkylbenzene is preferably reduced using a rhodium or ruthenium catalyst. These catalysts ensure a minimum of hydrogenolysis.

The conditions regarding catalyst, solvent, reaction temperature, hydrogen pressure and reaction time (although these quantities are probably not independent of one another) are considered to be non-critical. However, it is advantageous to use a 5% rhodium-on-aluminum catalyst in amounts of 0.5 to 10% by weight of the ketone used. The hydrogenation is conveniently carried out at temperatures between 25 ° C and 60 ° C and at pressures between 30 psi and 300 psi (1 psi = 0.068 atm.).

The use of a solvent is optional. The hydrogenation can accordingly be carried out with or without a solvent. Suitable solvents are, for example, ethanol, acetic acid, pentane, etc. The information regarding the amount of catalyst, temperature range, pressure and solvent are only for illustration and should not be regarded as a limitation of the invention.

Alternatively, the ketone can be hydrogenated in two stages, the carbonyl group first being reduced to an alcohol group. Methods which are known (for example the use of NaBH4, LiAlH4, normal catalytic reduction, etc.) can be used, and the resulting benzyl alcohol can be hydrogenated, a rhodium catalyst being used as mentioned above.

According to methods B and C of the reaction scheme, the 1-acetyl-4-t-alkylcyclohexene can be converted to the new alcohol I using various methods known for the hydrogenation of cc, β-unsaturated ketones to alcohols. For example, a two-step process can be used, first hydrogenating one of the two unsaturated bonds. However, it is advantageous to convert the 1-acetyl-4-t-alkylcyclohexene into the desired alcohol in a 1-step process.

The conditions for the 1-step process with regard to catalyst, solvent, reaction temperature, hydrogen pressure and reaction time do not appear to be critical (but the parameters are probably interdependent). A number of catalysts are known with which a, β-unsaturated ketones can be converted into saturated alcohols; it is platinum. Palladium, Ra-nay-Nickel, Rhodium, Ruthenium etc.

It is preferable to use the economical Raney nickel. With this process, the conditions of temperature, solvent, pressure and amount of catalyst are not critical.

The catalyst is preferably used in an amount which corresponds to approximately 5-15% of the ketone used. The preferred temperature range is from 80 ° C to 120 ° C and the preferred pressure range is between 60 psi and 600 psi. Solvents can be used, but this is not mandatory. If such solvents are used, those with low vapor pressure are preferably used. Again, the specified conditions with regard to temperature, pressure and amount of catalyst are illustrative and should be understood as non-limiting, because it has been shown that conditions which are far outside the specified ranges can still be used. It must be noted that the fact that the cis isomer of the reaction product is present in excess using Raney nickel as a catalyst is surprising. When the other hydrogenation methods are used, this usually results in a reaction mixture which consists of ice and trans isomer in equal parts. When using Raney nickel, the corresponding ratio is approximately 2-3 to 1.

According to method D, the 4-t-alkylcyclohexyl-carboxaldehyde is reacted with a suitable metal alkyl CH3M using the known methods required for this. Preferably, the aldehyde is slowly added to a solution of the metal alkyl in a suitable inert solvent and, after the reaction has ended, the primary reaction product is decomposed with a proton source, such as an acid.

The above-mentioned metal alkyl is preferably a Gri-gnard reagent (for example CH3MgX, where X is chlorine, bromine or iodine) or lithium alkyl (CH3Li), that is to say reagents which are commercially available or can be prepared by methods known per se.

An ether, such as ethyl ether, THF, etc., or an ether-hydrocarbon mixture, such as ethyl ether-toluene, THF-toluene, THF-benzene, etc., is preferably used as the solvent. The methodology is known in and of itself.

The new compounds of the present invention can be used as fragrances, for example in perfumes, soaps and other toiletries. They are particularly, although not exclusive, suitable as substitutes or partial substitutes for natural sandalwood oil.

This fact is extremely surprising since the compounds of the formula I which are monocyclic are compounds which have no structural relationship to the known a- and β-santalol, and yet the outstanding, fine and valuable natural sandalwood oil have reminiscent odorant properties. The new connections are extremely strong. The valuable odor properties can still be determined on the olfactory strip after several days.

It was also found that all compounds of Formula I have the sandalwood note.

The new compounds of the present invention can accordingly be mixed with perfume oils, concentrates and other chemicals used in perfumery to give the resulting formulations sandalwood notes. The most important use is based on completely or partially replacing the natural sandalwood oil in said formulations.

The following examples serve to illustrate the invention.

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Unless otherwise noted, the temperatures are given in ° C. The infrared bands are given in cm "1. The NMR spectra were recorded in chloroform-d!, The signals in 5 units relative to TMS (0.0 given), the molecular weights were determined by mass spectroscopy. For analysis purposes, gas was also taken -chromatographic methods used.

example 1

A. Process for the preparation of t-alkylcyclohexanones

The following procedure for the preparation of 4- (3-methyl-pent-3-yl) cyclohexanones serves as an illustration of the synthetic route for this class of compounds. The other t-alkylcyclo-hexanones can be prepared in an analogous manner.

1. Preparation of 4- (3-methylpent-3-yl) cyclohexanone a) Preparation of 4- (3-methylpent-3-yl) phenol

A mixture of 396 g (4.2 mol) of phenol, 230 g (2.25 mol) of 3-methyl-3-pentanol, 50 g (0.43 mol) of 85% phosphoric acid and 1.5 liters of benzene is refluxed and the azeotropically distilling water was collected in a Dean strong trap (53 ml). The reaction mixture is cooled and placed in a separatory funnel. The lower, lower layer is separated and the upper organic layer is washed with 500 ml portions of water until the pH of the wash water is 7. The solvent is removed using a rotary evaporator. Distillation of the remaining oil under vacuum leads to the desired 4- (3-methylpent-3-yl) phenol: 365 g 91% yield; Bp 112 ° C / 1.0 mm Hg; MG 178 (MS); NMR, 0.68 (6H, t, J = 8 2-methyl), 1.26 (3H, s, methyl), 1.4-2.0 (4H, m, -CH2-), 6.28 ( 1H, s, hydroxyl), 6.8-7.3 (4H, m, aromat.); IR, 3260, 2980, 2940, 2890, 1615, 1600, 1515, 1466, 1380, 1250, 1190, 1120, 830 cm-1.

b) Preparation of 4- (3-methylpent-3-yl) cyclohexanol

A mixture of 365 g (2.05 mol) of 4- (3-methylpent-3-

yl) phenol, 600 g of ethanol, 5 g of acetic acid and 8 g of 5% rhodium on activated carbon is hydrogenated at a pressure of 100 PSI and a temperature of 60 ° C. until the hydrogen absorption essentially ceases. The reaction mixture is filtered to remove the catalyst and the solvent is evaporated on a rotary evaporator. The resulting oil is washed with 200 ml of 10% sodium bicarbonate solution, then with 200 ml portions of water until the wash water has a pH of 7. Distillation of the crude oil under vacuum leads to the desired 4- (3-methylpent-3-yl) cyclohexanol: 350 g, 93% yield; Bp 110-115 ° C / 2.0 mm Hg; MG 184 (MS); NMR, 0.4-0.9 (9H, methyl), 1.0-1.5 (14H, m, CH2), 2.39 (1H, s, hydroxyl), 4.0 (IH, m, Ha to 0); IR, 3350,2980, 2950,2890, 1455,1385,1075,1046,960 cm-1.

c) Preparation of 4- (3-methylpent-3-yl) cyclohexanone

The 350 g (1.9 mol) of the 4- (3-methyl

pent-3-yl) cyclohexanoIs are slowly added within 3 hours to a stirred mixture of 614 g (2.06 mol) of sodium bichromate, 3 liters of water and 526 g of 98% sulfuric acid, taking care that the reaction temperature between 50 and 55 ° C. After the addition has ended, the mixture is stirred at 50 ° C. for a further hour. The reaction mixture is cooled and 3 liters of benzene are added. The layers are separated and the organic layer washed with 1 liter portions of water until the wash water has a pH of 7. The solvent is removed using a rotary evaporator. Distillation of the remaining oil under reduced pressure leads to the desired 4- (3-methylpent-3-yl) cyclo-

hexanone: 274 g 79%; Bp 105: C / 0.5 mm Hg; MG 182 (MS); NMR, 0.75 (3H, s, methyl), 0.8 (6H, t, J = 7, methyl), 1.15-2.0 (9H, m, CH, CH2), 2.15-2 , 5 (4H, m, Ha to CO); IR, 2980, 2890, 1720, 1465, 1390, 1170 cm "1.

2. In the same way, other t-alkylcyclohexanones can be prepared using the corresponding tertiary alcohols as starting materials. In this way they are synthesized.

a) 4- (2-Methylpent-2-yl) cyclohexanone bp. 88-90 ° C / 1.0 mm Hg b) 4- (3-ethylpent-3-yl) cyclohexanone bp. 79-80 ° C / 0 , 3 mm Hg c) 4- (l-methylcyclopentyl) cyclohexanone bp. 110 ° C / 0.5mmHg d) 4- (l-methylcyclohexyl) cyclohexanone bp. 47-8 ° C (solid)

The postulated structures are confirmed by IR, NMR and MS spectra.

B. Preparation of l-acetyl-4-t-alkylcyclohexenes For illustration purposes, the preparation of l-acetyl-4- (3-methyl-pent-3-yl) cyclohexene follows. The other l-acetyl-4-t-alkylcyclohexenes can be prepared in an analogous manner.

1. l-Acetyl-4- (3-methylpent-3-yl) cyclohexene 43 g (0.236 mol) of 4- (3-methylpent-3-yl) cyclohexanone are added to a stirred mixture of 23 g of lithium acetylide in 300 ml of benzene 3 hours added. 500 ml of water are then added dropwise and the mixture is kept at the reflux temperature for 1 hour. The mixture is cooled and the layers separated. The aqueous phase is extracted with ether. The combined organic layers are washed with water, dried over magnesium sulfate, filtered and concentrated under reduced pressure. Distillation of the remaining oil leads to the ice and trans-4- (3-methylpent-3-yl) l-ethynyl-cyclohexanol: 45.2 g, 76.9% yield, b.p. 86-90 ° Cj 0.5 mm Hg; NMR, 2.63 (1H, s, ethynyl H), 0.7-1.0 (9H, methyl H); IR 3380.3300, 1064 cm "1.

A solution of 30 g (0.14 mol) of ice and trans-4- (3-methylpent-3-yl) -l-ethynylcyclohexanol and 300 ml of 85% formic acid are kept at the reflux temperature for 2 hours. The mixture is then cooled. An excess of 10% sodium hydroxide solution is added (dropwise) and the mixture is then extracted using ether. The ethereal extract is washed with water, dried over magnesium sulfate, filtered and concentrated under reduced pressure. Distillation of the remaining oil leads to l-acetyl-4- (3-methylpent-3-yl) cyclo-hexene: 16.7 g, 56% yield; Bp 84-86 ° C / 0.15 mmHg; MG 208 (MS); NMR, 6.45 (1H, broad, vinyl.H), 2.25 (3H, see acetyl-methyl), 0.8-1.0 (9H, methyl H); IR, 1662.1639, 1385.1248.1068.964.907 cm-1.

2. In an analogous manner, other 1-acetyl-4-t-alkyl-cyclohexenes of the present invention are prepared using the corresponding ketones. These are the following:

a) 1-Acetyl-4- (2-methylpent-2-yl) cyclohexene b.p. 82-4 ° C / 0.15 mm Hg b) 1 -acetyl-4- (3-ethylpent-3-yl) cyclohexene bp . 95-100 ° C / 1.0 mm Hg c) I -acetyl-4- (l -methylcyclopentyl) cyclohexene bp. 88-90 ° C / 0.3 mm Hg d) l-acetyI-4- (l- methylcyclohexyl) cyclohexene bp. 92-100 ° C / 0.15 mm Hg

The structure of the above compounds are confirmed by IR, NMR and MS spectra.

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C. Preparation of l- (a-hydroxyethyl) -4-t-alkylcyclohexanes from the corresponding l-acetyl-4-t-alkylcyclohexenes

The process for the preparation of 1 - (a-hydroxyethyl) -4- (3-methylpent-3-yl) cyclohexane serves as an illustration. The other l- (a-hydroxyethyl) -4-t-alkylcyclohexanes can be prepared in an analogous manner.

1. l- (a-Hydroxyethyl) -4- (3-methylpent-3-yl) cyclohexane from I -acetyl-4- (3-methylpent-3-yl) cyclohexane

A mixture of 96 g (0.46 mol) of l-acetyl-4- (3-methyl-pent-3-yl) cyclohexene and 5 g of Raney nickel (activated by repeated washing with methanol) is at 100 ° under pressure hydrogenated by 300 PSI hydrogen pressure until the hydrogen uptake ceases (0.923 moles of hydrogen consumed). After the filtration, the crude l- (a-hydroxyethyl) -4- (3-methylpent-3-yl) cyclohexane is distilled, with a product in 95% yield consisting of 56% from the cis isomer and 44 % consists of the trans isomers, results: bp 82-83 / 0.15 mm Hg; MG 212 (MS); NMR, 0.66 (3H, s, methyl) 0.71 (6H, t, J = 7, methyl), 1.05-1.85 (14H, m, CH2, CH), 1.96 (1H, s, hydroxyl), 3.46 (q, J = 7, Ha to 0, cis-isomer), 3.88 (m, Ha to 0, trans-isomer); IR, 3360, 2980, 2940, 2890, 2880, 1460, 1385, 940 cm-1.

2. The other l- (a-hydroxyethyl) -4-t-alkylcyclohexanes of the present invention can be prepared in an analogous manner if the corresponding l-acetyl-4-t-alkylcyclohexenes are used as a starting point. These are the following:

a) 1 - (a-hydroxyethyl) -4- (2-methylpent-2-yl) cyclohexane; Bp 95-100 ° C / 1 mm Hg; MG 212 (MS); NMR 0.75 (s, methyl) 0.8-1.9 (m, -CH2, CH, methyl a at 0), 2.08 (1H, s, hydroxyl), 3.43 (m, Ha at 0 , cis isomer), 3.86 (Ha to 0, trans isomer); IR, 3380,2980,2940,2880,1475,1455, 1390,1370,1070,940 cm-1.

b) 1 - (a-hydroxyethyl) -4- (3-ethylpent-3-yl) cyclohexane; Sp / 120-130 ° C / 0.5 mm Hg; MG 226 (MS); NMR, 0.7-0.95 (m, methyl), 1.0-1.9 (m, CH2, CH, methyl a to hydroxyl), 1.9 (1H, s, hydroxyl), 3.5 ( m, Ha to hydroxy cis isomer), 3.9 (m, Ha to hydroxyl, trans isomer); IR, 3350,2980, 2940,2890,1655,1380, 1075,940 cm-1.

c) 1 - (a-hydroxyethyl) -4- (l -methylcyclopentyl) cyclo-hexane; Bp 114-120 ° C / 0.5 mm Hg; MG 210 (MS); NMR 0.81 (3H, s, methyl on cyclopentyl), 1.0-1.8 (m, CH2, CH, methyl a to hydroxyl), 1.71 (1H, s, hydroxyl), 3.5 (m , Ha to hydroxyl, cis isomer), 3.9 (m, Ha to hydroxyl trans isomer); IR, 3360.2950.2870.1455.1380.1070.940 cm-1.

d) 1 - (a-hydroxyethyl) -4- (1-methylcyclopentyl) cyclo-hexane; Bp 130-140 ° C / 1.0 mm Hg); MG 224 (MS); NMR, 0.73 (3H, s, methyl) 0.9-1.8 (23H, m CH2 CH, methyl a to hydroxyl), 1.75 (1H, s, hydroxyl), 3.51 (m, Ha to hydroxyl, cis-isomer), 3.91 (m, Ha to hydroxyl, trans-isomeres); IR, 3380, 2940,2870,1455,1380,1070,940 cm "1.

Example 2

This and the following examples illustrate the uses of the compounds of the present invention in fragrance compositions.

The compounds of the present invention are particularly valuable in the creation of synthetic sandalwood oil substitutes or sandalwood specialties. In the following formulation, X denotes a compound I of the present invention or the odorless diethyl phthalate. The diethyl phthalate is used in order to be able to characterize the corresponding formulation without the compound I.

X

Sandela® [polycyclic alcohol product with a smell of sandalwood, 50% in diethyl phthalate]

Amyris oil

American. Cedarwood oil

Parts by weight 200

700 50 50

1,000

10th

X can represent any of the new compounds of the present invention. Each of these compounds makes a corresponding contribution to the smell of the composition. With each attempt of the compositions with and without the connection X, the difference is immediately evident.

While each of the new compounds - compared to one another, there are subtle differences - contributes to the smell, the smell of the composition without the compound X is always weaker and less reminiscent of the natural sandalwood oil.

The compounds with the more intense odor are particularly preferred for formulations: 1- (a-hydroxyethyl) -4- (2-methylpent-2-yl) cyclohexane, 1- (a-hydroxyethyl) -4- (3-25 methylpent-3) -yl) cyclohexane or l- (a-hydroxyethyl) -4- (l-methylcyclopentyl) cyclohexane.

Other analogues, for example l- (a-hydroxyethyl) -4- (1-methylcyclohexyl) cyclohexane, 1 - (a-hydroxyethyl) -4- (3-ethylpent-3-yl) cyclohexane etc., are expediently 30 in higher concentrations used, namely 30-40% of the formulation.

The above wording and the discussion of olfactory properties are for illustration only. It is easy for the trained perfumer to choose the X that best serves his needs. In this way, he can benefit the most from the subtle nuances of the olfactory properties of the individual compounds. In general it can be said that the new Verbin-40 fertilizers are best used in amounts of approx. 10-60 percent by weight.

Example 3

45 The following example serves to illustrate the use of the compounds of the formula I in fragrance compositions of the woody type. Again, X stands for any of the new compounds of formula I or for an equivalent amount of the odorless diethyl phthalate.

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Parts by weight

Compound X

280

Orange liquid (a-methylnaphthyl ketone)

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Lime

38

Linalool

66

Linalyl acetate

95

Benzyl acetate

20th

y-methyl ionone

152

p.tert.-butyloyclohexyl acetate

114

Vetiveryl acetate

115

Coumarin

40

1,1,4,4-tetramethyl-6-ethyl-7-acetyl

1,2,3,4-tetrahydronaphthalene

30th

Aldehyde C-12.10% in dipropylene glycol

4th

Undecalactone, 10% in dipropylene glycol

6

Diphenyl oxide

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Diphenylmethane

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1000

637612

A composition containing l- (a-hydroxyethyl) -4- (3-methylpent-3-yl) cyclohexane is compared with a composition containing diethyl phthalate instead of the new X. The odor effect achieved with compound X corresponds to that which can be achieved by adding sandalwood oil. The woody character of the composition becomes fuller and richer.

The other compounds of the present inventions give similar results. X can also be used in higher concentrations in order to achieve special effects in such compositions.

Example 4

This example illustrates the use of the sandalwood bodies of the present invention in woody / floral type fragrance compositions. As above, X means either Compound I or the odorless diethyl phthalate.

Parts by weight

Connection X 300

Amyl cinnamaldehyde 21 aldehyde C-12 (lauryl), in 10%

Dipropylene glycol 8

Benzyl propionate 25

Bergamot (natural) 22

Methylpehnylcarbinylacetate 14

Linalool, cœur 35

Ylang bourbon extra 14

y-methyl ion 100

Jasmine (synthetic) 35 a-methyl-ß- (p-tert-butylphenyl) propion-

aldehyde 70

p-tert-butylcyclohexyl acetate 97

Vetiveryl acetate 97

3,7-dimethyl-7-octenol 56 1,1,4,4-tetramethyl-6-ethyl-7-acetyl-

1,2,3,4-tetrahydronaphthalene 56

Undecalactone, 10% in dipropylene glycol 8

1000

The formulation containing X (e.g. 1- (a-hydroxyethyl) -4- (1-methylcyclopent-1-yl) cyclohexane is compared to a formulation containing diethyl phthalate instead of X. The smell of the composition with one of the new sandalwood bodies is richer and softer than the composition without this compound I. The effect achieved by I is usually that which is achieved by adding natural

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chem sandalwood oil could be achieved. Analogously, other new I can be used in such compositions.

s Example 5

The example illustrates the use of the new I in violet-type fragrance composition. Again X stands for a new compound I or for the odorless diethyl phthalate.

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Components parts by weight

X

142

Aldehyde C-9, (n-nonanal)

ls 10% diethyl phthalate

2.3

Aldehyde C-10, (n-decanal) 10% in DAP

1

Amyl cinnamaldehyde

13

Benzyl acetate, benzyl salicylate

25th

20th

20 cinnamon acetate

45

Cyclamenaldehyde (a-methyl-p-isopropyl-

phenylpropionaldehyde)

10th

Citronelly acetate

30th

Phenyl-methyl-carbinyl-acetate,

25 10% in DAEP

45

Hexyl cinnamaldehyde

20th

Indole, 2,3-benzylpyrrole, 10% in DAEP

4th

Laurin® (hydroxycitronellal)

120

Linalool, coeur

140

30 linalyl cinnamate

40

Nerol, prime

40

Phenylethyl alcohol

130

Phenylethyl isobutyrate

4th

Phenylethyldimethylcarbinol

10th

35 phenylethylphenylacetate

25th

Rhodinol, extra

60

Rhodinylacetate

34

Terpineol

50

Tetrahydrolinalool

30th

40

1000

By adding the new l- (a-hydroxyethyl) -4- (l-methylcyclopent-l-yl) cyclohexane (example for X), the composition is given naturalness, woody and base notes in particular. It causes the flower to smell in its natural environment. The effect is the same as that achieved by adding natural sandalwood oil. Compositions in which diethyl phthalate is added instead of X do not have the effects described above. The other new compounds I 50 can be used for the same purposes.

Claims (17)

637 612 PATENT CLAIMS 1. Compounds of the formula wherein R, a tert. C6 or C7 alkyl radical, the tert. C atom is attached to the cyclohexane ring. 2. Compounds according to claim 1, wherein Ri represents an ali-cyclic t-C6 or -C7-alkyl radical or an aliphatic t-C7-alkyl radical. 3. 1 - (a-Hydroxyethyl) -4- (2-methylpent-2-yl) cyclohexane, as a compound according to claim 1. 4.1 - (a-Hydroxyethyl) -4- (3-methylpent-3-yl) cyclohexane as a compound according to claim 1. 5. 1 - (a-Hydroxyethyl) -4- (1 -methylcyclopent-1-yl) cyclo-hexane as a compound according to claim 1. 6.1 - (a-Hydroxyethyl) -4- (1-methylcyclohex-1-yl) cyclohexane as a compound according to claim 1. 7. l- (a-Hydroxyethyl) -4- (3-ethylpent-3-yl) cyclohexane as a compound according to claim 1. 8. Process for the preparation of compounds of the general formula ç j_j. qj_j 3rd or 15 20 wherein Rj is a tert. C6 or C7 alkyl radical, the tert. C atom is attached to the cyclohexane ring, characterized in that a compound of the formulas or IIa in which R, as defined above, is hydrogenated. 9. fragrance compositions containing a compound in which Rj is a tert. C6 or -C7 alkyl radical, the tert. C atom is attached to the cyclohexane ring. 10. fragrance composition according to claim 9, characterized in that it contains a compound of the formula I, in which R represents an alicyclic t-C6- or-C7-alkyl radical or an aliphatic t-C7-alkyl radical. 11. fragrance composition according to claim 9, characterized by a content of l- (a-hydroxyethyl) -4- (2-methylpent-2-yl) cyclohexane. 12. Fragrance composition according to claim 9, characterized by a content of l- (a-hydroxyethyl) -4- (3-methylpent-3-yl) cyclohexane. I b II c 4o 13. Fragrance composition according to claim 9, characterized by a content of l- (a-hydroxyethyl) -4- (l-methylcyclopent-1-yl) cyclohexane. 14. fragrance composition according to claim 9, characterized by a content of l- (a-hydroxyethyl) -4- (l- 45 methylcyclohex-1-yl) cyclohexane. 15. fragrance composition according to claim 9, characterized by a content of l- (a-hydroxyethyl) -4- (3-ethylpent-3-yl) cyclohexane. 50 16. Use of the compounds of formula I according to claim 1 as fragrances. 17. Use according to claim 16 of the compounds of the formula I according to claim I, in which Rj is an alicyclic t-C6- or-C7-alkyl radical or an aliphatic t- 55 represents C7-alkyl radical, according to claim 24. 18. Use according to claim 16 of 1- (a-hydroxyethyl) -4- (2-methylpent-2-yl) cyclohexane as a fragrance. 19. Use according to claim 16 of 1- (a-hydroxyethyl) -4- (3-methylpent-3-yl) cyclohexane as a fragrance. 60 20. Use according to claim 16 of l- (a-hydroxyethyl) -4- (l-methylcyclopent-l-yl) cyclohexane as a fragrance. 21. Use according to claim 16 of I- (a-hydroxy-ethyI) -4- (I-methylcyclohex-l-yl) cyclohexane as a fragrance. 22. Use according to claim 16 of l- (cc-hydroxy- 65 ethyl) -4- (3-ethylpent-3-yl) cyclohexane as fragrance. 3rd 637 612