Sulfuric Acid → 1-Cyclohexyl-5-methylhex-5-en-2-one

Participants

Reaction Conditions

Reaction Steps

A 250 ml flask was charged with 15.0 g of methyl 4-cyclohexyl-3-oxobutanoate (96% GC, 1 molar equivalent) and 9.8 g of methallyl chloride (1.5 molar equivalent). The mixture was heated to 70° C. and over the course of 90 minutes 13 g of a 30% solution of sodium methylate in methanol (1 molar equivalent) was added. Stirring was continued for 30 minutes and then 50 g of toluene was added. Within 1 hour 19.3 g of a 30% aqueous sodium hydroxide solution was added and stirring continued for 1 hour. After cooling to 25° C., 28.4 g of a 50% aqueous sulfuric acid solution was added over the course of 1 hour. To the slurry 70 g toluene and 40 g water were added and after decantation, the aqueous phase was drained. After concentration the crude product was fractionated leading to 8.9 g of 1-cyclohexyl-5-methylhex-5-en-2-one (95% GC, 60% yield).

Provenance & Evidence