Rhodium-Catalyzed Enantioselective [2 + 2 + 1] Cycloaddition of 1,6-Enynes with Cyclopropylideneacetamides.

It has been established that a cationic rhodium(I)/( R)-tol-BINAP or ( R)-BINAP complex catalyzes the enantioselective [2 + 2 + 1] cycloaddition of 1,6-enynes, possessing monosubstituted alkene units, with cyclopropylideneacetamides at room temperature through the elimination of ethylene to give bicyclic (cyclopent-2-en-1-ylidene)acetamides with high enantioselectivity.