No abstract

New silicon , germanium , and tin containing imido alkyl molybdenum complexes (ArN) 2 Mo(CH 2 EMe 3 ) 2 (Ar is 2,6 diisopropylphenyl; E = Si (1), Ge (2), Sn (3)) were prepared in the crystalline state in 58-66% yields by the reactions of the (ArN) 2 MoCl 2 (DME) com plex with alkyllithium derivatives Me 3 ECH 2 Li (E = Si or Ge) or the Grignard reagents Me 3 ECH 2 MgCl (E = Ge or Sn). The structures of complexes 1-3 and the known analog (ArN) 2 Mo(CH 2 Bu t ) 2 (4) were established by X ray diffraction analysis. Complexes 1-3 were found to be isostructural. The coordination environment about the Mo atom can be described as a distorted tetrahedron. Complex 4 has a similar structure. The Mo-C distance tends to decrease with increasing electron donating ability of the EMe 3 group.

Heterobimetallic tert-butoxides (t-BuO) 5 Cu 2 Ln (Ln = Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb), (t-BuO) 5 MLa (M = Mn, Fe, Co, Ni), (t-BuO) 5 ZnNd, and (t-BuO) 4 ZnFe were prepared in high yields by the reaction of t-BuOLi with a stoichiometric mixture of a lanthanide halide LnX 3 (Ln = Y, La, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb; X = Cl, I) and a d-transition metal salt MX n (M = Zn, Cu, Mn, Fe, Co, Ni; X = Cl, Br). (t-BuO) 5 Cu 2 Ln (Ln = Y, La, Nd, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb) and (t-BuO) 5 ZnNd at room temperature and atmospheric pressure induce copolymerization of CO 2 with cyclohexene oxide, affording the polycarbonate in a yield of 33 6 g g 31 catalyst. The complex (t-BuO) 5 FeLa, and also iron alcoholates (t-BuO) 2 Fe and (t-BuO)2 F e(bipy) under similar conditions catalyze the reaction of CO 2 with propylene oxide affording monomeric propylene carbonate in a yield of 353 45 g g 31 catalyst.

The reaction of Et 2 Zn with NaOCH 2 CH 2 OH yielded a bimetallic zinc complex NaOCH 2 CH 2 .