Furan ring recyclization in 2-furfurylthieno[2,3-b]pyridines: An intramolecular N-alkylation of pyrrole ring under acid conditions

Abstract

(Chemical Equation Presented) The preparation of new 3-amino-2- furfurylthieno[2,3-b]pyridines (1a,b, 69-80%) is described. Subsequent acidic rearrangement of 1a,b afforded two new annulated heterocyclic products, 5a,b, pyrrolothieno[2,3-b]pyridines (45-74%), and 6, pyridothieno[2,3-b]pyrrolizine (22%), depending on reaction conditions. © 2010 HeteroCorporation.