Synthesis of 1‐azacycl[3.2.2]azine and 1‐azabenzo[h]cycl[3.2.2]azine

Abstract

1‐Azacycl[3.2.2]azines were synthesized from 2‐methylthioimidazo[1,2‐a]pyridines, 2a and 2b, by using [2 + 8] cycloaddition reaction with dimethyl acetylenedicarboxylate as the key step. Synthesis of 1‐azabenzo‐[h]cycl[3.2.2]azine was also described.

Indolizines and Their Hetero/Benzo Derivatives in Reactions of [8+2] Cycloaddition

“…Soon it was proved also for 8-aza-indolizine 60a and its 7-oxo-analog 61b [ 85 ]. 1-Azaindolizine bearing 2-SO 2 Me group failed to go in such cycloaddition [ 86 ], whereas the same structures with 2-SMe group 61a , b [ 87 ] and their [h]-benzannelated derivatives 62 [ 88 ] formed the desired azacyclazines with DMAD. In our recent work, we proved that MAC could react with 1-azaindolizine 63 giving azacyclazine in the open air [ 36 ].…”