Aryl(7-indolizinyl)methanes

Aryl(6-methyl-2-phenyl-7-indolizinyl)methanes were obtained by quaternization of aryl(γ-pyridyl)methanes with bromoacetophenone and subsequent cyclization of the quaternary salts with 40% potassium carbonate solution (the Chichibabin method). The stable 2, 5-dimethyl-4-(2,4-dimethylbenzyl)pyridinium benzoylmethylid, which was converted to an indolizine by the action of Al2O3, was isolated by the action of a 10% potassium carbonate solution on the corresponding quaternary salt. The ability of 3-unsubstituted indolizines to undergo protonation in both the 3 and 1 position was shown on the basis of the PMR spectra. The aryl(7-indolizinyl)methanes are selectively hydrogenated thoroughly over rhenium heptasulfide in the indolizine ring to give tetra or octahydro derivatives without involvement of the aryl groups. Data from the IR, PMR, and mass spectra are presented. © 1977 Plenum Publishing Corporation.