Copper-Catalyzed Cascade Cyclization for the Synthesis of Trifluoromethyl-Substituted Spiro-2H-azirines from 1,6-Enynes

A method for the synthesis of trifluoromethyl CF3-substituted spirocyclic compounds containing with a unique quaternary carbon center from readily available starting materials has been developed. The reaction provides a facile access to 2H-azirines via cascade cyclization. These compounds constitute a new class of functionalized synthetic intermediates, which can be used for the synthesis of various nitrogen-containing heterocycles and biologically active CF3-containing compounds.