The thermolysis of polyazapentadienes. Part 4. Formation of indoles and quinoxalines from 5-(2,6-disubstituted phenyl)-1,2,5-triazapentadienes and related compounds

Abstract

7-Methylindole and 5-substituted quinoxalines are the principal cyclised products from the gas-phase thermolyses of the hydrazones (2) and (5) and of the oxime ether (7). Both heterocyclic systems arise by competitive decomposition of the spirodienyl radical, e.g.(18), the indole by loss of MeCN and a hydrogen atom, and the quinoxalines by loss of a methyl radical.