Titanium(IV) Chloride Catalyzed Cyclopropanations of Alkenes Using Zinc Dust, Copper(I) Chloride, and Dihalomethanes

Article abstract of DOI:10.1021/jo00271a027

The addition of catalityc amounts of titanium(IV) chloride greatly facilitates the cyclopropanation reactions of alkenes with dibromomethane using zinc dust and copper(I) chloride in ether.The rate of reaction and yields of cyclopropane products obtained from alkenes not bearing Lewis acid sensitive functional groups are as good or better than those found by using dibromomethane with ultrasound promotion.They are also comparable to those obtained by using diiodomethane under various conditions.