Process of production of 1-(5,5-dimethylcyclohex-1-en-1-yl)ethanone and 1-(5,5-dimethylcyclohex-6-en-1-yl )ethanone

Abstract

The present invention relates to an improved method for producing of 1-(5,5-dimethylcyclohex-1-en-1-yl)ethanone and 1-(5,5-dimethylcyclohex-6-en-1-yl)ethanone.

Claims

1. A process for producing compounds of formula (I): ##STR00022## wherein the process comprises conducting a catalyzed rearrangement reaction at an elevated temperature of 30 C. to 120 C. of a compound of formula (II): ##STR00023## wherein the rearrangement reaction is catalyzed by at least one Au(I)-complex.

2. The process according to claim 1, wherein the at least one Au(I) complex is a compound of formula (III):
YAu(I)Z(III), wherein Z is an anion which is selected from the group consisting of [BX.sub.4].sup., [PX.sub.6].sup., [SbF.sub.6].sup., [ClO.sub.4].sup., CF.sub.3COO.sup., sulfonates, tetra(3,5-bis(trifluoromethyl) phenyl)borate (BAr.sub.F.sup.), tetraphenylborate, and an anion of formula (IV): ##STR00024## wherein Q represents a phenyl or a C.sub.1-8-alkyl; X is a halogen atom, and Y is an organic ligand.

3. The process according to claim 2, wherein the organic ligand Y of the Au(I) complex of formula (III) is selected from the group consisting of: ##STR00025## ##STR00026##

4. The process according to claim 2, wherein the anion Z of the Au(I) complex of formula (III) is an ion selected from the group consisting of [BF.sub.4].sup., [PF.sub.6].sup., [SbF.sub.6].sup., [ClO.sub.4].sup., CF.sub.3COO.sup., sulfonates, tetra(3,5-bis(trifluoromethyl)phenyl)borate (BAr.sub.F.sup.), tetraphenylborate, and the anion of formula (IV): ##STR00027##

5. The process according to claim 1, wherein the process is carried out in a solvent or a mixture of solvents.

6. The process according to claim 5, wherein the solvent is selected from the group consisting of methanol, ethanol, 2-butanol and tert-butanol.

7. The process according to claim 1, wherein Au(I)-complex is used in an amount to provide a ratio of the compound of formula (II) to catalyst which is from 2:1 to 10000:1.

8. The process according to claim 2, wherein Q represents a C.sub.1-8-alkyl which is substituted by at least one substituent selected from the group consisting of F, Cl and NO.sub.2.

9. The process according to claim 2, wherein X represents F or Cl.

10. The process according to claim 1, wherein the catalyzed rearrangement reaction is carried out at an elevated temperature of 40 C. to 110 C.

11. The process according to claim 1, wherein the catalyzed rearrangement reaction is carried out at an elevated temperature of 50 C. to 100 C.

Description

EXAMPLES

Example 1: Rearrangement of 1-ethynyl-3,3-dimethylcyclohexanol

(1) ##STR00017##

(2) 118.8 mg (0.2 mmol, 0.1 equiv.) of dicyclohexylphosphine biphenyl gold(I)-chloride and 56.88 mg (0.2 mmol, 0.1 equiv.) of silver triflate were dissolved under argon at 23 C. in 5.0 ml of tert-butanol in a septum bottle. 362.6 l (90%, 2 mmol, 1 equiv.) of 1-ethynyl-3,3-dimethylcyclohexanol (90%, 2 mmol, 1 equiv.) were added. The reaction mixture was stirred for 105 min at 80 C. Afterwards the reaction mixture was cooled to 23 C. A sample was taken out and analyzed by GC and NMR.

(3) The conversion of this reaction was 98.9%. The products of formulae (I and I) were obtained in a yield of 89.6 wt-%.

(4) It is possible to separate the two isomers if desired.

Examples 2-6

(5) The following examples were carried out under the same reaction condition as in example 1.

(6) The ligands are defined as above and the ligands are added in the chloride form and the anions in the form of the Ag(I) salt.

(7) TABLE-US-00001 conversion yield Exp. ligand anion [%] [%] 2 Y.sup.2 SbF.sub.6.sup. 98.6 78.3 3 Y.sup.2 95.4 88.9 4 Y.sup.2 98.7 89.1 5 Y.sup.3 BF.sub.4.sup. 78.5 40.8 6 Y.sup.3 0 75.6 41.9

Comparative Examples (Examples 7-11)

(8) The same reaction as described in Example 1 was repeated, but Au catalysts, which do not fall under the scope of the claims were used.

(9) Example 7 and 8 are carried out without any organic ligands. AuCl was used in combination with the silver salt

(10) TABLE-US-00002 conversion yield Exp. ligand anion [%] [%] 7 BF4.sup. 16.8 0 8 5.3 3.1

(11) Example 9, 10 and 11 and 8 are carried out with catalysts where Au(0) is adsorbed on a carrier.

(12) TABLE-US-00003 conversion yield Exp. Cat [%] [%] 9 Au/TiO.sub.2 2.9 0 10 Au/Al.sub.2O.sub.3 4.8 0 11 Au/C 4.6 0

(13) Therefore it can be seen that the choice of the suitable (claimed) catalyst is essential.