Urea → 5-Benzyloxazol-2-amine

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-bromo-3-phenyl-propionaldehyde (26.0 g, purity 60%, 0.0732 mol) in ethanol (300 ml) was added urea (14.66 g, 0.244 mol) and the reaction mixture was heated to 90° C. for 12 h. The solvent was evaporated, the residue was diluted with dichloromethane and washed with aqueous sodium hydroxide solution (2 N) and water. The organic phase was extracted three times with aqueous hydrochloric acid solution (2 N). The combined aqueous phases were adjusted to pH 10 with aqueous sodium hydroxide solution (2 N) and then extracted three times with dichloromethane. The combined organic phases were dried over sodium sulfate, the solvent was evaporated and the residue purified by silica gel chromatography using dichloromethane/methanol as eluent. The title compound was obtained as a yellow solid (1.78 g, 14%). MS ISP (m/e): 175.2 (100) [(M+H)+].

Provenance & Evidence