Synthesis and X-ray Crystal Structures of Tetranuclear Zincamidinate Complexes

Polynuclear amidinate zinc halide complexes of the general type{C[C(Ni-Pr)2ZnX]4} [X = Cl, 2; Br, 3; I, 4] were prepared in high yields via methyl/halide exchange reaction of {C[C(Ni-Pr)2ZnMe]4} (1a) with AlX3. 2−4 were characterized by elemental analysis, multinuclear NMR, and IR spectroscopy and single-crystal X-ray diffraction. Computational calculations of halide-substituted complexes {C[C(Ni-Pr)2ZnX]4} [X = F−I] were performed to clarify the influence of the halide atom on the structural parameters of the complexes and to elucidate their electronic structure and bonding situation. The capability of these halide-substituted complexes to serve as suitable starting reagents for further salt elimination reactions was proven by reaction of 2 with LiR (R = Me, n-Bu) and EtMgBr, which yielded the corresponding Zn-alkyl species {C[C(Ni-Pr)2ZnR]4} [R = Me, 1a; n-Bu, 5; Et, 6].