2-(3,3-dimethylbutyl)cyclopentan-1-one

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: At 0° C., aq. sodium carbonate solution is added to a solution consisting of 20.0 g of (119 mmol) of 2-(3,3-dimethylbutyl)cyclopentanone and 16.5 g (238 mmol) of hydroxylamine hydrochloride in 200 ml of methanol until the pH is 8. The mixture is then stirred at 50° C. for 15 hours. After the reaction has ended, the mixture is cooled to room temperature and filtered off and the product is concentrated under reduced pressure. The residue is extracted with water/diethyl ether. The org. phase is dried with sodium sulphate and concentrated under reduced pressure. This gives 20.0 g (92% of theory) of an 2-(3,3-dimethylbutyl)-N-hydroxycyclopentanimine. the mixture is cooled to room temperature filtered off the product is concentrated under reduced pressure The residue is extracted with water/diethyl ether phase is dried with sodium sulphate concentrated under reduced pressure

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution consisting of 23.0 g (101.7 mmol) of methyl 1-(3,3-dimethylbutyl)-2-oxocyclopentanecarboxylate in 80 ml of acetic acid and 80 ml of conc. hydrochloric acid is stirred at 90° C. for 14 hours. After the reaction has ended, the mixture is cooled to room temperature and ice-water is added. The product is extracted with diethyl ether. The org. phase is washed with water, dried with sodium sulphate and concentrated under reduced pressure. The crude product is purified by column chromatography (silica gel 60-120, mobile phase: ethyl acetate 3%/petroleum ether). This gives 10 g (59% of theory) of 2-(3,3-dimethylbutyl)cyclopentanone. the mixture is cooled to room temperature The product is extracted with diethyl ether phase is washed with water dried with sodium sulphate concentrated under reduced pressure The crude product is purified by column chromatography (silica gel 60-120, mobile phase: ethyl acetate 3%/petroleum ether)