Benzaldehyde → 2-Benzylidenecyclohexanone

Participants

Reaction Steps

A 500-ml four-necked flask equipped with a thermometer was charged with 53 g of benzaldehyde, 25 ml of water and 1 g of sodium hydroxide, to which 68 g of cyclohexanone were added dropwise at 30° C. over 30 minutes. The resultant mixture was stirred for 1 hour at the same temperature. After neutralizing the reaction mixture to separate liquid layers from each other, the resultant reaction product was dissolved in 500 ml of toluene. To the solution, 0.5 g of PTS (p-toluenesulfonic acid) was added to conduct azeotropic dehydration for 3 hours in a 1-liter four-necked flask equipped with a Dean-Stark trap and a thermometer. After cooling, the residue was neutralized and washed with water, and the resultant organic layer was dried and concentrated, thereby obtaining 119 g of a crude product. This product was purified by column chromatography to obtain 24 g (yield: 28%) of 2-benzylidenecyclohexanone.

Provenance & Evidence