Zinc-Mediated Carbene Insertion to C-Cl Bonds of Chloromethanes and Isolable Zinc(II) Isocyanide Adducts

The zinc adduct {[HB(3,5-(CF3)(2)Pz)(3)]Zn}(+) which was generated from [HB(3,5-(CF3)(2)Pz)(3)]ZnEt and [Ph3C]{B[3,5-(CF3)(2)C6H3](4)}, catalyzes the activation of C-halogen bonds of chloromethanes via carbene insertion. Ethyl diazoacetate serves as the carbene precursor. The presence of {[HB(3,5-(CF3)(2)Pz)(3)]Zn}(+) in the reaction mixture was confirmed by obtaining {[HB(3,5-(CF3)(2)Pz)(3)]Zn(CN(t)Bu)(3)}(+) using CN(t)Bu as a trapping agent. {[HB(3,5-(CF3)(2)Pz)(3)]Zn(CN(t)Bu)(3)}(+) loses one zinc-bound CN(t)Bu easily to produce five-coordinate {[HB(3,5-(CF3)(2)Pz)(3)]Zn(CNt u)(2)}(+).