The thermolysis of heterocyclic aminimines

Aminimines derived from six heterocyclic tertiary amines were thermolyzed in t-butyl alcohol at ca. 80°. N-Methylindoline gave a good yield of the ring-opened product, and a double elimination on 1,4,4-trimethyl-piperidine gave 3,3-dimethyl-1,4-pentadiene. The aminimine derived from quinuclidine was stable to elimination under these conditions. Simple elimination products were not obtained from N-methyl-pyrrolidine, N-methylpiperidine, or N-methyltetrahydroisoquinoline.