4-tert-Butylcyclohexanone

OccurrenceHas apparently not been reported to occur in nature.

Uses4-tert-Butylcyclohexanone is used as a perfuming agents and in cosmetic. This material, commercially available for almost two decades, has only temporarily gained some importance as a powerful, “lifting” soap perfume ingredient, or as an in-expensive additive to Patchouli notes for soap and detergent fragrances, etc. It has more power and much less tenacity than Cedarwood and Patchouli, which is only an advantage in certain types of household products, where tenacity is not always very desirable. The title ketone can also give powerful “lift” to certain types of floral fragrance and to most of the herbaceous ones, Lavender, Lavandin, Rosemary, etc.

PreparationBy hydrogenation of p-ferr-butylphenol. Care must be taken that no free p-tert-butylphenol remains, because it is a sensitizer and depigmenting agent(Opdyke, 1974).

PreparationN-Chlorosuccinimide (NCS) (8.0 g, 0.060 mol) and toluene (200 mL) were cooled to 0 C° in a 1-L, threenecked, round-bottomed flask equipped with a mechanical stirrer, a thermometer, a dropping funnel, and an argon inlet tube. Dimethyl sulfoxide (6.0 mL, 0.10 mol) was added and the mixture was cooled to -25 C° using a tetrachloromethane/dryice bath. A solution of 4-tert-butylcyclohexanol (6.24 g, 0.04 mol; mixture of E and Z isomers) in toluene (40 mL) was added dropwise over 5 min, stirring was continued for 2 h at -25 C°, and then a solution of triethylamine (6.0 g, 0.06 mol) in toluene (10 mL) was added dropwise over 3 min. The cooling bath was removed, and, after 5 min, diethyl ether (400 mL) was added. The organic phase was washed with 1% aq. hydrochloric acid (100 mL) and then with water (2 × 100 mL), and dried over anhydrous magnesium sulfate. The solvents were evaporated under reduced pressure, and the residue was transferred to a 50-mL, round-bottomed flask and bulb-to-bulb distilled at 120 C° (25 mmHg) to yield 5.72 g (93%) of 4-tertbutylcyclohexanone 1794; mp 41–45 C°. Recrystallization from petroleum ether at -20 C° gave an 88% recovery of 1794 with mp 45–46 C°.