Iodoethane → 5-Ethyl-2-methoxy-3,4-dimethyl-2-cyclopenten-1-one

Participants

Reaction Conditions

Reaction Steps

22.80 g (165 mmol) of potassium carbonate and 0.69 g (3 mmol) of benzyltriethylammonium chloride are suspended in 150 ml of acetonitrile. While stirring 32.42 g (150 mmol) of methyl 4-methoxy-2-(1-methylacetonyl)-acetoacetate are added thereto and the mixture is heated to 60° C. 28.08 g (180 mmol) of ethyl iodide are added thereto within 100 minutes and the mixture is stirred at 60° C. for a further 90 hours. The suspension is then poured into a solution of 10.35 g (75 mmol) of potassium carbonate in 450 ml of water and heated at reflux temperature for 30 hours. The cooled reaction solution is extracted 3 times with 300 ml of CH2Cl2. The combined organic phases are dried over magnesium sulphate and concentrated on a rotary evaporator. The crude product is distilled at 20 mbar/97°-99° C. and gives 3.61 g (14.3%) of 5-ethyl-2-methoxy-3,4-dimethyl-2-cyclopenten-1-one.

Provenance & Evidence