Spontaneous Si-C bond cleavage in (Triphos)-nickel complexes.

Herein, we report on the versatile reactions of CHC(CHPPh) as well as CHSi(CHPPh) derived Ni-complexes. While Ni[CHC(CHPPh)] complexes reveal high stability, the Ni[CHSi(CHPPh)] analogs show rapid decomposition at room temperature and afford the unprecedented pseudo-tetrahedral phosphino methanide complex 5. We provide a detailed electronic structure of 5 from X-ray absorption and emission spectroscopy data analysis in combination with DFT calculations, as well as from comparison with structurally related complexes.

Controlled Flexible Coordination in Tripodal Iron(II) Phosphane Complexes: Effects on Reactivity.

The possibility to alter properties of metal complexes without significant steric changes is a useful tool to tailor the reactivity of the complexes. Herein we present the synthesis of iron complexes with the tripodal phosphane ligands Triphos and Triphos(Si) and report on their different coordination properties. Whereas reaction of Triphos(Si) and FeX2 (X = Cl, Br) exclusively afforded (Triphos(Si))FeX2 with a κ(2)-coordinated ligand, the homologous C-derived Fe complexes show rapid conversion in solution to afford [(Triphos)Fe(CH3CN)3][Fe2Cl6] or [(Triphos)Fe(CH3CN)3][FeBr4], respectively.