Scheme 3.
Synthesis of 4-(3-Chlorophenoxycarbonylamino)butyric Acid Ethyl Ester (10)a
a Reagents: (a) triphosgene, aq NaHCO3/dichloromethane, rt; (b) 3-chlorophenol, triethylamine, DMF, rt.
Synthesis of 4-(3-Chlorophenoxycarbonylamino)butyric Acid Ethyl Ester (10)a
a Reagents: (a) triphosgene, aq NaHCO3/dichloromethane, rt; (b) 3-chlorophenol, triethylamine, DMF, rt.