Insertion Reactions of Heterocumulenes into Zn−C Bonds: Synthesis and Structural Characterization of Multinuclear Zinc Amidate Complexes

Reactions of ZnMe2 with isocyanates RNCO proceeded with insertion of the isocyanate into the Zn−Me bond, giving the corresponding heteroleptic amidate complexes [MeZnOC(Me)NR]x (R = i-Pr (1), t-Bu (2)) and [{MeZn}4Zn{OC(Me)NC6F5}6] (3) in high yields. In contrast, ZnCp*2 reacts with isocyanates and isothiocyanates with formation of homoleptic complexes of the type [Zn{OC(Cp*)NR}2]2 (R = Et (4), i-Pr (5)) and [Zn{SC(Cp*)N-i-Pr}2]2 (6). 1−6 were characterized by elemental analyses, multinuclear NMR (1H, 13C, 19F) and IR spectroscopy, and single-crystal X-ray diffraction (1, 2, 5).