The carbamoylation of some lactams derivatived from pyroglutamic acid as been studied; better yields were obtained starting from the unsubstitued lactam (toluene, 80°) rather than starting with the N-silyllactam (room temperature), although these latter reaction conditions could be interesting for heat sensitive compounds. Methyl and phenyl isothiocyanate react only with the sodium salt of methyl pyroglutamate
Synthesis, Decarboxylation, and Nitrosation of 1-Acyl-2-pyrrolidone-3-carboxylic Acids: A Convenient Novel Entry to 2,3-Dioxopyrrolidine Derivatives
作者:Viktoras Gailius、Helmut Stamm
DOI:10.1002/ardp.19923250207
日期:——
Esters 1 of 1‐acyl‐2‐pyrrolidone‐3‐carboxylic acids 2 were hydrolized to 2 with acetic acid/HCl at 60–70°C. Reaction of 1a with formic acid/HCl at 60–75°C led to (not isolated) 2a which began to decarboxylate to 3a during the conversion of 1a to 2a even at this low temp. Decarboxylation of 2c‐f was accomplished at 160°C without solvent. Decarboxylative nitrosation of 2c‐f yielded the oximes 4c‐f of 1‐acyl‐2