Tandem transformations of tetrahydrobenzothieno[2,3-c]pyridines in the presence of activated alkynes

The reactivity of some new tetrahydrothienopyridines towards activated alkynes was investigated. A novel cascade cleavage-spiroannulation process, leading to the formation of previously unreported derivatives of 1′H-spiro[1-benzothiophene-3,4′-pyridine] was discovered and studied. © 2010 Elsevier Ltd. All rights reserved.