360073-14-9Relevant academic research and scientific papers
Group 5 imido complexes supported by diamido-pyridine ligands: Aryloxide, amide, benzamidinate, alkyl, and cyclopentadienyl derivatives
Pugh, Stephen M.,Tr?sch, Dominique J.M.,Skinner, Michael E.G.,Gade, Lutz H.,Mountford, Philip
, p. 3531 - 3542 (2001)
A family of new organometallic and coordination group 5 compounds supported by an imido-diamido-pyridine ligand set are reported. Reaction of [M(NR)Cl(κ3-N2Npy)(py)] (M = Nb, R = tBu 1; M = Ta, R = tBu 2 or Ar 3, where N2Npy = MeC(2-C5H4N)(CH2NSiMe3)2 and Ar = 2,6-C6H3iPr2) with LiOAr or LiPhC(NSiMe3)2 afforded the five-coordinate aryloxide and benzamidinate complexes [M(NR)(OAr)(κ3-N2Npy)] (R = tBu, M = Nb 4 or Ta 5; R = Ar, M = Ta 6) and [Nb(NtBu){PhC(NSiMe3)2}(κ3- N2Npy)] (7), respectively. Reaction of 1 or 2 with LiN(SiMe3)2 or LiCH(SiMe3)2 gave the four-coordinate compounds [M(NtBu)(X)(κ2-N2Npy)] (M = Nb, X = N(SiMe3)2 8 or CH(SiMe3)2 9; M = Ta, X = CH(SiMe3)2 10). Reaction of 1 or 2 with the less sterically demanding alkyl reagent LiCH2SiMe3 gave, in the case of niobium, only the four-coordinate [M(NtBu)(CH2SiMe3)(κ2- N2Npy)] (11), but for tantalum an equilibrium mixture of four- (κ2-) and five- (κ3-) coordinate isomers was identified by NMR spectroscopy. Reaction of 1 with PhCH2MgCl or LiC5H4Me gave the corresponding η1- or η5-hydrocarbyl complexes [Nb(NtBu)(CH2Ph)(κ3-N2 Npy)(py)] (13) and [Nb(NtBu)(η5-C5H4Me)- (κ2-N2Npy)] (14). The X-ray crystal structures of the compounds 4, 6, and 9 are reported.
