Transition Metal Free Nucleophilic Benzylation of Nitroarenes. Umpolung of the Friedel Crafts Reaction
Benzyl chloride and its derivatives are efficiently deprotonated with strong bases to form α-chlorocarbanions. These anions are long-lived enough to enter VNS reactions with nitroarenes or nitroheteroarenes to give a variety of unsymmetrical o- and p-nitrodiarylmethanes. Selectivity of the reaction can be controlled to some extent by changing metal counterions of the base. (Figure presented.).