Ammonia → benzyl N-(2-carbamoylethyl)carbamate

Participants

Reaction Conditions

Reaction Steps

111.7 g of benzyloxycarbonyl-β-alanine were dissolved in 1 liter of dimethylformamide, cooled to -20° C, treated with 70 ml of triethylamine and 67 ml of chloroformic acid isobutyl ester and stirred at -20° C for 3 minutes. Dry ammonia gas was led into this mixture until the pH rose to 11, care being taken that the temperature did not, exceed -10° C. The mixture was stirred for a further 30 minutes at room temperature, filtered and the filtrate concentrated in vacuo. The residue was recrystallised from water. Yield: 91 g; melting point 162°-165° C.

Provenance & Evidence