Synthesis of indolizines and pyridinium ylids from 4,5-disubstituted α-picolines

New 1,3-diacetylindolizines were obtained from 4-phenyl- and 4-benzyl-2,5-dimethylpyridines; some transformations involving their acetyl groups were realized. The same pyridine bases were used in syntheses of pyridinium ylids. The transformations of the latter to indolizines were studied. © 1977 Plenum Publishing Corporation.