An Improved Synthesis of Some 5-Substituted Indolizines Using Regiospecific Lithiation. // Molecules, 2005, 10(9), 1074-1083

Various 2-substituted indolizines can be directly and selectively lithiated in the 5 position and subsequent reactions with different electrophiles lead to some novel classes of indolizines. In particular, previously unknown 5-formyland 5-iodoindolizine have been prepared by this way and the molecular structure of 5-formyl-2phenylindolizine was confirmed by X-Ray analysis. The reactivity of the 5-CHOand 5COPh groups toward some nucleophiles has been examined, and some additional classes of derivatives (oximes and alcohols) have been obtained. The possibility of Suzuki crosscoupling of 5-iodoindolizines and boronic acids was proven.