Dicyclohexylamine → N-benzyloxycarbonyl-(L)-pyroglutamic acid chloride

Participants

Reaction Conditions

Reaction Steps

50 g (0.113 mol) of the previously obtained dicyclohexylamine salt of N-benzyloxycarbonyl-(L)-pyroglutamic acid are mixed to a paste with 1 liter of toluene, 110 ml of thionyl chloride are run in dropwise and the temperature is then raised to 60° C. for 2 hours. The mixture is cooled and filtered, the filtrate is evaporated and the residue is taken up several times with benzene. The acid chloride finally crystallizes from petroleum ether with a practically quantitative yield. Melting point=65°-70° C. (literature=71/72° C.).

Provenance & Evidence