DE1082250B - Process for the production of cis-1-acyloxy-3, 7-dimethyl-octenen- (2) which are characterized by special odorant properties and are optionally methyl-substituted in the 6-position - Google Patents

Description

Process for the production of cis-l-acyloxy-3,7-dimethyl-octenen- (2) which are characterized by particular odorant properties and are optionally methyl-substituted in the 6-position. Position methyl-substituted cis-1-acyloxy-3,7-dimethyl-octenen- (2). The new compounds mentioned have the following general formula: in which R represents hydrogen or a methyl group and acyl represents the acyl radical of a carboxylic acid.

The new compounds have an intense odor and can be used as a Fragrances are used for the production of perfumes.

The term "cis" as used herein denotes the steric configuration of the a, ß-double bond, which corresponds to that of geraniol.

The process for the preparation of the above-mentioned novel compounds consists in the fact that 3,7-dirnethylocten- (1) -ol- (3) which is methyl-substituted in the 6-position converted into the corresponding 1-hydrohalic acid ester with allyl rearrangement, this by heating in an inert solvent with an alkali acetate in the converts unsaturated 1-acetoxy compound, the latter to the corresponding unsaturated one 1-alcohol saponified and the 1-alcohol with an acylating agent to form the 1-acyloxy compound esterified.

The process according to the invention is represented by a formula below, where R is hydrogen or a methyl group and "acyl" is the acyl radical of a carboxylic acid, e.g. B. an alkanoyl radical, such as octanoyl or palinitoyl, or a monocyclic aroyl radical, such as benzoyl or toluoyl, denotes: One of the two starting materials II is the known compound 3,7-dimethyl-oeten- (1) -ol- (3). The other starting material, namely 3,6,7-trimethyl-octen- (1) -ol- (3), can in a manner not claimed here by methods known per se from 5,6-dimethyl-heptanone- (2) by acetylene addition and subsequent partial hydrogenation of the triple bond can be obtained.

In the first stage of the process according to the invention, the starting material is ff suitably with a concentrated aqueous hydrohalic acid, e.g. B. about 370% hydrochloric acid or about 480% hydrobromic acid.

Uni the halogen in the inorganic ester III obtained in this way in the to replace the second process stage with an acetoxy group, the ester is in an inert solvent, -, vie acetone, with an alkali acetate, e.g. B. potassium acetate, warmed up.

The ice-l-acetoxy-3,7-dimethyl-oetene- (2) formed, optionally methyl-substituted in the 6-position becomes in the next stage to eis-3,7-dimethyl-oeten- (2) -ol- (1) or eis-3,6,7-trimethyl-octen- (2) -ol- (1) [VJ hydrolyzed, expediently by saponification using an aqueous alcoholic Potassium hydroxide solution. The re-esterification of the obtained unsaturated 1-alcohols takes place by reaction with an acylating agent, e.g. B. with an acid or their acid chloride or their anhydride.

A process is preferred in which the unsaturated 1-alcohols of the formula V are treated with an acylating agent containing no more than 8 carbon atoms. Examples of acyl esters which can thus be introduced are lower alkanoyl groups such as propionyl, isobutanoyl, cycloalkanoyl groups such as cyclohexanecarbonyl or cyclopentanecarbonyl, aroyl groups such as benzoyl or toluoyl. The unsaturated 1-esters obtained in this way have particularly pleasant odor nuances.

From British patent specification 678 121 it is already known to treat myrcene (a hydrocarbon containing three double bonds) with hydrogen chloride or hydrogen bromide, to convert the halogen-containing oetadiene obtained into the corresponding unsaturated carboxylic acid ester by reaction with the alkali salt of a lower fatty acid, and thus to convert it into known fragrances to get. In contrast, the process according to the invention differs significantly in that a monounsaturated tertiary alcohol is used as the starting material, the halogen substituent is not introduced by addition to a double bond, but by substitution with allyl rearrangement and, in addition, new fragrances with advantageous odor nuances are obtained.

It is further known from US Patent 2,359,164 to halogenate a tertiary alkenol with allylic rearrangement, umzuestern the halogen compound with an alkali metal acetate to the acetyl compound and the latter to the alcohol, d. H. in this case to saponify to vitamin A. The present process differs from this process, which proceeds with the formation of the therapeutically active vitamin A and related compounds, in particular in that it leads to novel fragrances.

Example 1 234 g of 3,7-dimethyl-octen- (1) -ol- (3) are mixed with 600 cc of 48 % aqueous hydrobromic acid in a 2-1 flask equipped with a mechanical stirrer. The mixture is stirred for 2 hours at room temperature. The oil layer is removed, washed twice with 500 cc of water and dried over anhydrous calcium chloride. The 1-bromo-3,7-dimethyl-octene (2) obtained has a specific refraction of n-'D5 = 1.4630. It is mixed with 3 liters of acetone and 400 g of anhydrous potassium acetate in a 5 l flask. The mixture is refluxed with stirring for 24 hours. Then, the acetone is distilled off under a pressure of 100 mm, and the remaining in the flask residue is taken up in 11 water. The separated oil is dried over anhydrous calcium sulfate and distilled in vacuo. The main fraction, consisting of 1 - acetoxy "3,7-thinethylocten- (2), distilled at 80'C / 1.4 mm; ib - ', 5 = 1.4424. This product is a colorless 01, which has a It is saponified to 3,7-thinethyl-octen- (2) -ol- (1) as follows: 102.5 g of 1-acetoxy-3,7-dimethyl-oeten- (2) become placed in a provided with a stirrer 1-1 flask with 500 cc of ethanol and a solution of 60 g potassium hydroxide in 120 cc of water. The mixture is stirred for 4 hours at 40'C and then diluted with 11 cold water, the oil layer is removed. and the aqueous part is extracted four times with 500 cc of ktroleum ether each time . The oil is combined with the extracts, washed neutral with water and the solvent is removed in vacuo. The main fraction consists of 3,7-dimethyl-octen- (2) -ol- (1) and distilled at 118 to 119 ° C / 20 mm; WD5 # 1.4522. This product has a pleasant fragrance reminiscent of fresh roses. It can, for example, be esterified as follows: a) 46.8 g 3,7-diine ethyl-octen- (2) -ol- (1) are stirred with 65 g of isobutyric anhydride and 100 cc of pyridine in a flask for 2 hours at 60 to 70 ° C. The reaction mixture is then washed with 500 ccm of water, 500 ccm of 5 % aqueous sulfuric acid, 500 ccm of 5 % aqueous sodium carbonate and again with 500 ccm of water. The oil obtained is dried over anhydrous calcium sulfate and fractionated through a column. The 1-isobutyroxy-3,7-diinethyl-octeri- (2) formed passes over at 74C / 0.3 mm, n2D5. = 1, 4 4 1 . This product has a pleasant scent that is reminiscent of roses and a bit like a freight ax.

b) A mixture of 50 g of 3,7-dimethyl-octen- (2) -ol- (1), 60 g of formic acid and 200 cc of petroleum ether are heated to boiling under reflux for 4 hours while stirring. The reaction mixture is then washed with 500 cc of water, 500 cc of 5 "/ aq Natriumbiearbonatlösung and again cc with 500 water. The 01 dried over anhydrous calcium sulfate and fractionated. The resulting 1-formyloxy-3,7-dimethylocten- (2 ) distilled at 80'C / 3 mm; iz2.5 = 1.443. It has a scent reminiscent of roses.

c) 78 g of 3,7-thinethyl-octen- (2) -ol- (1) and 100 cc of pyridine are placed in a flask equipped with a stirrer. 70 g of benzoyl chloride are added dropwise over the course of 15 minutes , the temperature rising to 80 ° C. Stirring is continued until the mixture has cooled to room temperature. The reaction mixture is then washed with 500 cc of water, 500 cc of 5 ″ aqueous sulfuric acid, 500 cc of 5 ″ aqueous sodium carbonate and again with 500 cc of water. After drying over anhydrous calcium sulfate, the product is fractionated The fraction boiling at C / 0.4 mm consists essentially of 1-benzoyloxy-3,7-dimethyl-octene-2; n2D5 = 1.501. This product has a rose-like odor.

EXAMPLE 2 156 g of 3,7-dimethyl-octen- (1) -ol- (3) are stirred for one hour with 500 cc of 37 % aqueous hydrochloric acid at room temperature. The oil layer is separated in a separating funnel, washed twice with 11 water and dried over calcium chloride, and the resulting 1-chloro-3,7-dirnethyl-octene (2) is mixed in a flask with 2 1 acetone and 270 g of anhydrous potassium acetate. The mixture is refluxed with stirring for 60 hours. The acetone is distilled off in vacuo and the residue is washed with 11 water. The separated oil is washed a second time with 500 cc water, dried over anhydrous calcium sulfate and fractionated. The fraction which distills at 89 ° C./8 mm consists essentially of 1-acetoxy-3,7-dimethyl-octene-2; n-'95 = 1.442. As indicated in Example 1 , this compound is reacted further. Example 3 A mixture of 255 g of 1,4,5-trimethyl-1-vinylhexanol- (1) and 600 cc. 480% hydrobromic acid is stirred at 15 ° C. for one hour. The oil layer is separated off in a separating funnel and washed three times with 200 ccm of water each time. After drying over calcium chloride, 3-18 g of 1-bromo-3,6,7-trimethyl-octene-2 are obtained; n- * D5 = 1.472. This product is refluxed with 3 l of acetone and 400 g of potassium acetate for 24 hours. Most of the acetone is removed by distillation. The residue is taken up in 1 liter of water. The oil layer is separated off in a separating funnel, dried over anhydrous calcium sulfate and fractionated. 104 g of 1-acetoxy-3,6,7-trimethyl-octene-(2) with a boiling point of 116 ° C / 20 mm, n2D5 = 1.446 are obtained. This compound has a scent reminiscent of roses. It is saponified to the unsaturated 1-alcohol as follows: A solution of 50 g of 1-acetoxy-3,6,7-trimethyloctene (2) in 500 cc of ethanol is mixed with 125 g of a 20% aqueous potassium hydroxide solution. The reaction mixture is stirred for 2 hours at 500 C, diluted with 11 water and extracted twice with 200 cc of petroleum ether. The combined extracts are washed neutral with water, dried over anhydrous calcium sulfate and fractionated. At 121 ° C./18 mm, 42 g of 3,6,7-Trünethyl-octen- (2) -ol- (1) distill; it2D-1 = 1.457. This compound has a rose-like scent. You can z. B. be esterified as follows: a) A solution of 85 g of 3,6,7-trimethyl-oeten- (2) -ol- (1), 100 g of formic acid and 400 ccm of n-heptene is refluxed for 2 hours while stirring warmed up. The reaction mixture is then washed with 500 cc of water, 500 cc of 5 0 /, aqueous sodium bicarbonate and with 500 cc of water. The oil formed is dried over anhydrous calcium sulfate and fractionated. At 13CPCi45 mm, 1-formyloxy-3,6,7-trimethyl-octene (2) distilled; W "5 = 1.449. It has a fragrance reminiscent of roses.

b) 34 g of 3,6,7-trimethyl-octen- (2) -ol- (1), 100 cc of pyridine and 48 g of isobutyric anhydride are stirred in a flask equipped with a stirrer, thermometer and heating bath for 4 hours at 60.degree . The reaction mixture is then washed with 500 cc of water, 200 cc of 5 O /, aqueous sulfuric acid, 200 cc of 5 O /, aqueous sodium carbonate and finally with 200 cc of water. The oil formed is dried over anhydrous calcium sulfate and fractionated. 1-Isobutyroxy-3,6,7-trimethyloctene-2 distills at 106'C / 1.5 mm; it2D5 = 1.4455. It has a scent reminiscent of roses with a fruity or musky component.

c) 85 g of 3,6,7-trimethyl-octen- (2) -ol- (1) and 100 cc of pyridine are placed in a flask equipped with a stirrer and thermometer. 70 g of benzoyl chloride are added dropwise over the course of 15 minutes. The temperature is allowed to rise to 80 ° C. and stirring is then continued until the mixture has cooled down to room temperature again. The reaction mixture is washed with 500 cc of water, 5 0 /, aqueous sulfuric acid, 500 CCIN 5 "/, washed aqueous sodium carbonate and 500 cc of water. The resulting oil is dried and fractionated. For 136'C / 0.3 mm distilled 1 -Benzoyloxy-3,6,7-trimethyl-octen- (2); n2D5 = 1.501. It smells faintly of roses. Example 4 170 g of 1,4,5-trimethyl-1-vinyl-hexanol- (1) and 500ccm 37 % aqueous hydrochloric acid is stirred for one hour at room temperature. The oil layer is then separated off, washed twice with 500 cc of water and dried over calcium chloride. The 1-chloro-3,6,7-trimethyl-octene (2 ) is boiled for 60 hours with 2 1 acetone and 300 g of anhydrous potassium acetate under reflux. most of the acetone is distilled off in vacuo. the residue is taken up in 11 of water, the separated oil is separated in a separating funnel, washed until neutral and dried. Fractionation of the dried oil gives this at 126 ° C./28 mm starting 1-acetoxy-3,6,7-trimethyl-octene (2); n2D-1 = 1.446 to 1.447. As indicated in Example 3 , this compound is reacted further.

Claims (3)

PATENT CLAIMS.- 1. A process for the production of cis-1-acyloxy-3,7-dimethyl-octene (2) which is optionally methyl-substituted in the 6-position and which is distinguished by particular fragrance properties, characterized in that 3 , 7-Dimethyl-octen- (1) -ol- (3) is converted into the corresponding 1-hydrohalic acid ester with allyl rearrangement, this is converted into the unsaturated 1-acetoxy compound by heating in an inert solvent with an alkali acetate, the latter to the corresponding unsaturated one 1-alcohol is saponified and the 1-alcohol is esterified with an acylating agent to give the 1-acyloxy compound. 2. The method according spoke 1, characterized in that the conversion of the optionally 6-methylated 3,7-dimethyl-octene (1) -ols- (3) in its hydrohalic acid ester is carried out by treatment with aqueous hydrohalic acid. 3. The method according to claim 1, characterized in that the unsaturated 1-acetoxy compound formed is saponified with the aid of aqueous-alcoholic potassium hydroxide solution and then treated with an acylating agent containing no more than 8 carbon atoms. References considered: British Patent No. 678 121; USA. Pat. No. 2,369,164.