Cyclohexanone → Cyclohexanecarboxylic acid, 2-oxo-, methyl ester

Participants

Reaction Conditions

Reaction Steps

To sodium hydride (60% oil dispersion, 10 g) was added a solution of dimethyl carbonate (18.02 g, 200 mmol) in dry THF (50 mL). The mixture was stirred at reflux temperature (100° C.), and then, a solution of cyclohexanone (7.8 g, 80 mmol) in dry THF (20 mL) was added dropwise to the mixture using a syringe pump. After two minutes of addition, potassium hydride (30% oil dispersion, 0.9 g) was added to initiate the reaction. The addition of cyclohexanone was continued over a period of 1 h. The mixture was refluxed and stirred for an additional 30 min after complete addition of cyclohexanone, when the reaction mixture lumped. It was cooled down in an ice bath for 20 min. The mixture was hydrolyzed by the slow addition of 3M aqueous acetic acid (75 mL), then poured into brine (100 mL) and extracted with CH2Cl2 (150 mL×4). The combined organic layers were dried over MgSO4 and filtered. The filtrate was evaporated in vacuo to give a thick yellow liquid (17.2 g). The liquid was distilled under reduced pressure to give 2 (11.3 g, 91%) as a colorless liquid [bp 38-43° C. (0.05-0.075 mm Hg, bath temp: 75-78° C.)]. See Ruest et al., 1976.

Provenance & Evidence