NEW SUBSTITUTED INDOLIZINES BY 1,3-DIPOLAR CYCLOADDITION REACTIONS. Part 2. 7-CYANOINDOLIZINES

The new indolizine derivatives 6a-e and 7a-e containing a cyano group grafted on the pyridinic ring were obtained by reaction of N-phenacylpyridinium bromides 3 with ethyl propiolate or 1-butyn-3-one as acetylenic dipolarophiles in medium of 1,2-epoxypropane. Structural proof for the compounds was provided by elemental analysis and NMR spectroscopy, including COSY and HETCOR experiments.