Acetic Acid → alpha-Cyanocinnamic acid ethyl ester

Participants

Reaction Steps

A mixture containing 4.0 mL (37.6 mmoles) of ethyl cyanoacetate, 3.95 g (37.2 mmoles) of benzaldehyde, 20 mg of β-alanine, and 1.00 mL of glacial acetic acid in 35 mL of benzene was heated at reflux for 3 hours with continuous azeotropic removal of water by means of a Dean-Stark trap. The product was isolated by cooling the mixture to room temperature, pouring it into 75 mL of 2:1 (v/v)1M aqueous NaOH:saturated brine, and extraction with ether. The organic extracts were washed with 75 mL of 2:1 (v/v) 1M aqueous NaOH:saturated brine, 10% aqueous sodium chloride solution, then were dried over anhydrous magnesium sulfate and subsequently filtered. Removal of the ether and benzene by evaporation at reduced pressure afforded 6.88 g (92% yield) of crystalline cyanoester 1: mp 49°-50° C.

Provenance & Evidence