L. Klemm, J. N. Louris, W. Boisvert
Sep 1, 1985
Citations
0
Influential Citations
14
Citations
Journal
Journal of Heterocyclic Chemistry
Abstract
Thieno[3,2-b]pyridine (1) is oxidized to N-oxide 1a by means of m-chloroperoxybenzoic acid (83%). Compound 1a forms adducts with hydrogen chloride and picric acid and gives ring substitution alpha or gamma to the heteronitrogen atom. Thus, 1a plus nitric and sulfuric acids produces the 7-nitro-N-oxide 1m (63%), or plus phosphorus oxychloride gives a mixture of 5-chloro and 7-chloro (1j) derivatives of 1. Compound 1m is convertible into a variety of other derivatives of 1, viz. 7-chloro-N-oxide, 1j, 7-bromo-N-oxide, 7-nitro and 7-amino. 5-Cyano-1, formed from 1a, is, in turn, transformed into a methyl imidate (93%), cyclic amidines, and a 5-tetrazolyl-1 (91%). These results confirm the prediction that 1a, thieno[2,3-b]pyridine-4-oxide and quinoline 1-oxide should exhibit closely similar (i.e. analogous) chemical reactions.