Simple Generation of Nonstabilized Azomethine Ylides through Decarboxylative Condensation of α-Amino Acids with Carbonyl Compounds via 5-Oxazolidinone Intermediates
Heating α-amino acids with a variety of carbonyl compounds generates N-unsubstituted or N-substituted azomethine ylides of nonstabilized types through the elimination of water and carbon dioxide. The ylides are captured by olefinic, acetylenic, and carbonyl dipolarophiles producing pyrrolidines, pyrrolines, and oxazolidines. The reaction involves intermediary 5-oxazolidinones which can be sometimes