Novel Ambiphilic Dichlorocarbenoid Equivalent in Alkene Cyclopropanation and Carbonyl Olefination

The Ti−Mg−dichloromethylene complexes derived from the oxidative addition of CCl<sub>4</sub> to the Mg−TiCl<sub>4</sub> bimetallic species serve as a novel class of ambiphilic dichlorocarbenoid equivalents. Not only is Ti−Mg−dichlorocarbenoid highly selective but also it seems highly reactive in both alkene cyclopropanations and carbonyl dichloromethylenations.