Acetic Acid → 2-(Propan-2-ylidene)cyclopentan-1-one

Participants

Reaction Steps

A mixture of 190 ml of acetone and 36.0 g of sodium hydroxide in 600 ml of water was treated with 60.0 g of cyclopentanone under stirring. After stirring for about 12 hours at about room temperature, the mixture was neutralized with 36% acetic acid and extracted with three 60 ml portions of ether. The combined extracts were dried over anhydrous magnesium sulfate and evaporated to give a residue. The residue was distilled to obtain 62.6 g of 2-(1-methylethylidene) cyclopentanone as a colorless liquid. The boiling point of this intermediate compound was determined to be 85°-88° C. at a pressure of 10 mm Hg. A subsequent Mannich reaction yielded the 2-Dimethylaminomethyl-5-(1-methylethylidene) cyclopentanone hydrochloride. The melting point of the product was determined to be 173°-175° C.

Provenance & Evidence