A Thioannulation Approach to Substituted Thiophenes from Morita-Baylis-Hillman Acetates of Acetylenic Aldehydes
Chada Raji Reddy*, Reddi Rani Valleti and Motatipally Damoder Reddy
*Division of Natural Products Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad-500007, India, Email: rajireddyiict.res.in
C. R. Reddy, R. R. Valleti, N. D. Reddy, J. Org. Chem., 2013, 78, 6495-6502.
DOI: 10.1021/jo400567h (free Supporting Information)
A mild, metal-free and base-promoted thioannulation of Morita-Baylis-Hillman acetates of acetylenic aldehydes with potassium thioacetate to yield substituted thiophenes involves a tandem allylic substitution/deacetylative 5-exo-dig-thiocycloisomerization. The obtained products provide an entry to 4H-thieno[3,2-c]chromene and thieno[3,2-c]dihydroquinoline.
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