NHSi/NHGe-Supported Copper Halide and Pseudohalide Complexes: Synthesis and Application

Herein, we have demonstrated the complexation reaction of silylene and germylene [PhC(NtBu)2EN(TMS)2; E = Si (A) and Ge (B)] with several copper(I) salts and further utilized them (1–6) as efficient catalysts in CuAAC reaction. The copper complexes (2 and 4–6) were synthesized from the reaction of [PhC(NtBu)2EN(TMS)2] [E = Si (A) or Ge (B)] and CuX (X = Br, I, and SCN). The molecular structures of 2, 4, 5, and 6 were established by single-crystal X-ray diffraction studies. The density functional theory studies indicate that the bimetallic Cu catalyst facilitates the cycloaddition reaction by anchoring the reactants to the close proximity and reducing the energy gap between the frontier orbitals of the dipole and dipolarophile.