Yb(OTf)3 catalyzed [3 + 2] annulations of D–A cyclopropanes with β-oxodithioesters: a regioselective synthesis of tetrahydrothiophenes†
Abstract
A new route to prepare tetrahydrothiophene derivatives from D–A cyclopropanes and β-oxodithioesters catalyzed by Yb(OTf)3 is reported. This is the first example using β-oxodithioesters as dipolarophiles to react with D–A cyclopropanes. The method exhibits good regioselectivity.