New monocyclopentadienyl complexes of group 4 and 5 metals with chelating nitrogen ligands. Crystal and molecular structures of [Zr(eta(3)-C3H5)(eta(4)-Ph2N2C2Me2-2,3)Cp ''] and [TaCl2{,eta(4)-C6H4C(NSiMe3-1,2)(2)}Cp ''] [Cp '' = C5H3(SiMe3)(2)-1,3]

摘要

Reduction of [MCl3Cp "] [M = Zr or Hf; Cp " = C5H3(SiMe3)(2)-1,3] with magnesium in the presence of 1,4-dipbenyl-2,3-dimethyl-2, 2,3-dimethyl-1,4-diazabuta-1,3-diene (DAD) gave the diazadiene complexes [MCl(DAD)Cp "] in high yield. Alkylation with RMgCl affords the alkyls [MR(DAD)Cp "] (R = CH3 or CH2Ph) and the more stable allyl complexes [M(eta(3)-C3H5)(DAD)Cp "] as yellow to light brown solids The reaction of Li-2[C6H4(NSiMe3)(2)-1,2] with [MCl4Cp "] leads to the bis(amido) complexes [MCl{C6H4(NSiMe3)(2)-1,2}Cp "], while the analogous reaction with [MCl4Cp "] (M = Nb or Ta) generates the red to red-brown niobium and tantalum half-sandwich compounds [MCl2{C6H4(NSiMe3)(2)-1,2}Cp "]. The crystal structures of two representative examples, [Zr(eta(3)-C3H5)(DAD)Cp "] and [TaCl2{C6H4(NSiMe3)(2)-1,2}Cp "], are reported. [References: 53]