Synthesis of Spirocyclic Oxindole Dihydrothiophenes by DBU-Catalyzed [3 + 2] Annulation of Morita-Baylis-Hillman Carbonates with Isothiocyanates.

J Org Chem

State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, P. R. China.

Published: November 2016

A highly regioselective DBU-catalyzed [3 + 2] annulation of Morita-Baylis-Hillman carbonates with isothiocyanates was developed. This method allows rapid and efficient synthesis of spirocyclic oxindole dihydrothiophene products in moderate to high yields with excellent regioselectivities under simple conditions. A plausible reaction mechanism is also proposed.

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http://dx.doi.org/10.1021/acs.joc.6b01315DOI Listing

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