DE960097B - Process for the preparation of new 4- [6'-alkyl-2 ', 6'-dimethylcyclohexen - (I' or 2 ') - yl - (1') -] - butene - (3) one- (2) - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

ISSUED MARCH 14, 1957

GERMAN PATENT OFFICE

PATENT LETTERING

JVr. 960 097 CLASS 12o GROUP 25 INTERNAT. CLASS C 07c

H 24897 IVb / 12 ο

Joseph Donald Surmatis, Pompton Plains, N. J. (V. St. A.)

has been named as the inventor

F. Hoffmann-La Roche & Co. Aktiengesellschaft, Basel (Switzerland)

Process for the preparation of new 4- [6'-alkyl-2 \ e'-dimethylcyclo-hexen-il 'or 2') - yl- (l ') -] - buten- (3) -onenr (2)

Patented in the territory of the Federal Republic of Germany from September 8, 1955 Patent application published September 27, 1956

Patent issued on February 28, 1957

The priority of registrations in the V. St. v. America September 13th and September 29th, 1954

and May 4, 1955 is claimed

The present invention is a process for the preparation of novel 4- [6'-alkyl-2 ', 6'-dimethylcyclohexen- (i' or 2 ') - yl- (i')] - ° ^NEN - ^buten - (3) - ( ² )> the valuable fragrances represent, the subject.

The method according to the present invention is characterized in that a ketone of the general formula

denotes atoms, is treated by means of an acidic cyclizing agent,

It. it is known that pseudojonon can be converted into α- and by the action of acidic cyclizing agents / 9-ionone can convert, depending on the cyclizing agent used and depending on the reaction conditions, mixtures with more or less of the

RC = CH-CH ₂ -CHa-C = CH-CH = CH-CO-CH ₃ , ² °

I ■ 'I'

CH ₃ CH ₃

in which R is an alkyl radical with 2 to 4 carbon- Jj one or the other component, et- or

/? - Jonon are well-known violet fragrances. In contrast the new process end products have peculiar, previously unknown odor notes, and they are distinguished from the ionons by their increased adhesive strength.

As starting materials for carrying out the process according to the invention, for. B. 6, io-dimethyldodecatriene- (3, 5, g) -on- (z) and 6, io, I2-trimethyltridecatriene- (3, 5, o.) - on- (2) can be used.

The 6, io-dimethyldodecatriene- (3, 5, g) -on- (2) can e.g. B. can be produced as follows:

6oo g of 3-methylpentene (i) -OL- (3) are cooled in a reaction vessel with an ice bath to-15 -f ^0, whereupon 1800 cm ³ concentrated aqueous, 37 ° / _o hydrochloric acid are poured to the reaction vessel. The mixture is stirred for 30 minutes. The resulting oil, consisting largely of i-chloro-3-methylpentene- (2), is separated off, ^{washed three times with 500 cm 3 of} water and dried over calcium chloride.

In a flask with a capacity of 12 liters, 1040 g Ethyl acetoacetate and 378 g of sodium methylate were stirred. Thereupon 696 g of i-chloro-3-methylpentene- (2), the preparation of which has been described above from a dropping funnel in the course of Added for 2 hours at 60 °. The mixture is stirred further at 60 ° overnight. The mixture is then diluted with 4 l of water, whereupon the oil formed is separated off and the benzene is removed under reduced pressure is distilled off. The thick residue consisting of 3-carbethoxy-6-methylocten- (5) -one- (2) becomes together with 2 liters of ethyl alcohol, 1 liter of water and 500 g of potassium hydroxide in a flask with a capacity of 5 liters. The mixture is stirred for 2 hours and then left to stand overnight. You get in this way the potassium salt of 3-carboxy-6-methylocten- (5) -one- (2).

Concentrated hydrochloric acid is added from a dropping funnel to the stirred reaction mixture until the mixture reacts strongly acidic. The oily layer is separated off, whereupon the aqueous portion is extracted with 1 liter of benzene. The oil obtained from the benzene extract is combined with the previously separated oil, whereupon the entire amount is washed with water and fractionally distilled. In this way 6-methylocten- (5) -one- (2) is obtained, which distills at 65710 mm; n ² j = 1.4412.

84 g of sodium metal are dissolved in 3 l of liquid ammonia. Acetylene is passed into the stirred solution until the initially blue-colored solution becomes colorless. A solution of 420 g of 6-methylocten- (5) -one- (2) in 500 cm ^{3 of} diethyl ether is added dropwise to the stirred reaction mixture over the course of one hour. The mixture is stirred for a further 3 hours while a gentle stream of acetylene is passed in. After the supply of acetylene has been interrupted, the reaction mixture is stirred for a further 15 hours. Then the ammonia is distilled off, and washed the remaining residue in the reaction vessel with 2 1 5 ° / _o aqueous sulfuric acid. The product obtained is then washed with water, dried over anhydrous calcium sulfate and fractionally distilled. This gives 3, 7-dimethylnonene- (6) -in- (i) -ol- (3), which distills at 89710 mm; «^ = 1.4612.

300 g of 3, 7-dimethylnonene- (6) -in- (i) -ol- (3), 30 g of a 5% lead-palladium catalyst applied to calcium carbonate (see Lindlar, Helvetica Chimica Acta, vol. 35 , 1952, p. 446) and 300 cm ^{3 of} petroleum ether are introduced into a flask equipped with a stirrer. The mixture is at 25 to 30 ⁰ and a hydrogen pressure of 1 atm. hydrogenated until 1.9 moles of hydrogen have been consumed. Fractionation of the hydrogenation product gives the 3,7-dimethylnonadiene- (i, 6) -ol- (3) boiling at 132786 mm; n% = 1.4603;

^{1500 cm 3 of} water, 250 g of sodium dichromate, 125 cm ^{3 of} glacial acetic acid, 200 cm ^{3 of} benzene and 125 g of 3,7-dimethylnonadiene- (i, 6) -ol are placed in a flask equipped with a stirrer, thermometer and dropping funnel and cooled by means of a cold water bath - (3) given. ^{A solution of 125 cm 3 of} concentrated sulfuric acid in 400 cm ^{3 of} water is added to the stirred reaction mixture in the course of 2 hours. During the addition of the sulfuric acid solution, the temperature is kept at .40 °. After the reaction mixture has been stirred for a further hour, 1 liter of water is added. After the oil layer has been separated off in a separating funnel, the aqueous layer is ^{extracted with 400 cm 3 of} benzene. The oil and benzene extracts are combined and washed neutral. The oil is distilled through a column under reduced pressure. 3,7-Dimethylnonadiene- (2,6) -al- (i) is obtained, which distills at 135 to 137725 mm; «^ = 1.4830. The semicarbazone of this compound melts at 159 ^° .

45 g of 3 »7-dimethylnonadiene- (i, 6) -al- (i), 50 g of aluminum isopropylate, 600 cm ^{3 of} acetone and 600 cm ^{8 of} benzene are introduced into a 2 liter flask and stirred for 24 hours at reflux temperature. The cooled reaction mixture is washed neutral first with dilute hydrochloric acid and then with water. After the benzene has been distilled off, the reaction product is fractionally distilled in a high vacuum. 6, io-dimethyldodecatriene- (3,5, 9) -one- (2), w |, boiling at 102 to 10370.2 mm, is obtained ⁵ = 1.5223. The 2,4-dinitrophenylhydrazone of this compound melts at xxf.

The other ketones which can be used as starting materials can also be obtained in an analogous manner be done by z. B. instead of 3-methylpentene (i) oil - "(3) 3,5-dimethylhexen- (i) -ol- (3) used. For the production of the starting materials Protection not sought within the scope of the present invention.

Depending on the acidic cyclizing agents used, cyclic ketones with a-ionone or / S-ion structure. So you can get ketones with / J-ion structure win if you combine the ketones of the above general formula with concentrated sulfuric acid Treated in the cold. If, on the other hand, the acidic cyclizing agent is syrupy phosphoric acid at room temperature or used at a slightly elevated temperature above room temperature, one arrives at cyclic ketones with a-ion structure.

The new cyclic ketones obtainable according to the invention have hitherto unknown, new odor notes and can be used for the production of odoriferous substance mixtures and perfumes.
The following examples are intended to illustrate the invention.

Example ι

A mixture of 350 g of concentrated sulfuric acid and 75 g of glacial acetic acid is cooled to -30 °. 100 g of 6, io-dimethyldodecatrien- (3, 5, 9) -one- (2) are added dropwise to this mixture, the temperature being kept between -20 and -30 °. The stiff, reddish colored mixture is warmed to 0 ° and stirred for 10 minutes. The reaction mixture is then poured onto 1500 g of crushed ice. The mixture is extracted with toluene, and the extract is washed with water, then washed with 20 ° / _o aqueous sodium hydroxide solution and finally with saturated sodium chloride solution containing a few drops of acetic acid. Upon fractionation, 4- [6'-ethyl-2 ', 6'-dimethylcyclohexen- (i) <yl- (i') -buten- (3) -one- (2) is obtained as one at 86.5 to 87.070 , 3 mm fraction distilling over; n ^z _D ⁵ - 1.5165. This compound has a violet-like, but at the same time weakly cedar-like odor. The 2,4-dinitrophenylhydrazone of this compound melts at 126 ^° .

Example 2

51.4 g of 6, io-dimethyldodecatrien- (3, 5, g) -one- (2) are added dropwise over 30 minutes with vigorous stirring to 386 g of 85% aqueous phosphoric acid, the temperature between 30 and 35 ^{0 is} held. The reaction product is ^{poured into 1500 cm 3 of} cold water, extracted with benzene and the extract obtained is subjected to steam distillation. The distillate is then extracted with benzene and the extract is fractionally distilled. The 4- [6'-ethyl-2 ', 6'-dimethylcyclohexen- (2') - yl- (i ')] - buten- (3) -one- (2) is obtained in the form of a at 7370.10 mm distilling fraction; nf = 1.497. The 2,4-dinitrophenylhydrazone of this compound melts at 160 °. The 4- [6 \ ethyl-2 ', 6'-dimethylcyclohexen- (2') - yl- (i ')] - buten- (3) -one- (2) has a pleasant odor reminiscent of violet roots.

Example 3

jo 94.6 g of freshly distilled 6, 10, 12-trimethyltridecatrien- (3, 5, 9) -one- (2), bp = 10470.1 mm, «^ = 1.515, are in the course of 30 minutes with a cm ³ syrupy 85 ° / _o aqueous solution of phosphoric acid was added 24 to 30 ⁰ held temperature 580th The mixture is then stirred for a further 5 minutes at 30 °. The mixture is then poured into 2.2 l of ice water. The upper layer is separated and the aqueous layer is ^{extracted twice with 500 cm 3 of} benzene. The benzene solution is washed neutral with water. The crude reaction product is subjected to steam distillation, whereupon the upper organic layer of the distillate is separated and the lower aqueous layer is ^{extracted with 100 cm 3 of} benzene. The organic layer is combined with the benzene extract and the benzene is distilled off under reduced pressure. The residue is fractionally distilled in a high vacuum. The fraction distilling over at 94 to '9770.2 mm consists of 4- [6'-isobutyl-2', o'-dimethylcyclohexen- (2 ') - yl- (i')] - buten- (3) -one- (2); n $ = 1.4958 to 1.4963. This product has a penetrating wood odor reminiscent of cedarwood and sandalwood and is suitable as a fragrance for the manufacture of perfumes.

Example 4

R - C - CH CHO - - CHF> A mixture of 700 g concentrated sulfuric acid and 150 g of glacial acetic acid to ■ - 30 ⁰ cooled. To the cooled mixture is added over 45 minutes at a between - 20 ⁰ -one held temperature 234 g of freshly fractionated 6, 10, i2 Trimethyltridecatrien- (3, 5 ', 9) (2), Kp - · 30 and. = 10470.1 mm, nf - 1.515, added. Since the solution becomes very thick, a powerful stirrer must be used. The mixture is warmed to 0 ° and stirred at this temperature for 10 minutes. It is then poured onto 3000 g of crushed ice. The mixture is left on its own until the ice has melted. The organic layer is then separated and the aqueous layer extracted with toluene. The organic layer and the toluene are combined and ³ of water, then ³ 20 ° / _o aqueous sodium hydroxide solution and finally with 500 cm ³ contains a saturated aqueous sodium chloride solution containing a few drops of acetic acid, washed with 500 cm 500 cm. The oil obtained is dried over anhydrous calcium sulfate, whereupon the solvent is evaporated and the residue is fractionally distilled. The fraction which distills over at 9270.3 mm consists mainly of 4- [6'-isobutyl-2 ', 6'-dimethylcyclohexen- (i') - yl- (i ')] - buten- (3) -one- ( 2); η ff == 1.505 to 1.507. This compound has an odor similar to that of 4- [6'-isobutyl-2 ', 6'-dimethylcyclohexen- (2') -yl- (i ')] -buten- (3) -one- (2) is, but differs from the latter in that it is not so strongly woody and has odor notes similar to leaf-green. The product obtained can be used as a fragrance in the manufacture of perfumed products. L15

Claims (1)

PATENT CLAIM: Process for the preparation of 4- [6'-alkyl-2 ', 6'-dimethylcycldhexen- (i' or 2 ') - yl- (i')] - buten- (3) -one- (2), characterized in that a ketone of the general formula = CH-CH = CH-CO-CH ₃ CH, in which R denotes an alkyl radical with 2 to 4 carbon atoms, known per se Way by means of an acidic cyclizing agent such as concentrated sulfuric acid in the cold or syrupy phosphoric acid at room temperature or at a temperature slightly higher than room temperature is treated. Considered publications: German patent specifications No. 129 027, 812 313, 10 933149; HeIv. Chim. Acta, Vol. 37, 1954, pp. 2196-2199; Vol. 32, 1949, pp. 2102-2124. © 6 »620 /« 5 9.5 «(609 835 3.57)