Regioselective insertion of 2-vinylpyridine in niobium and tantalum aryloxide complexes: an alternate route to pyridylalkyl metallacycles.

A series of niobium and tantalum aryloxide complexes containing pyridylethyl ligation have been synthesized via 2-vinylpyridine insertion to metal hydride complexes.

The nature of aryloxide and arylsulfide ligand bonding in dimethyltitanium complexes containing cyclopentadienyl ligation.

A series of dimethyltitanium compounds [CpTi(EAr)Me2](E = O, S) ligated by one cyclopentadienyl (Cp) and one aryloxide (OAr) or arylsulfide (SAr) have been structurally characterized in order to gain a better understanding of aryloxide and arylsulfide bonding in these systems. Experimental structures were compared to those predicted by density functional theory (DFT). Bonding in the arylsulfide systems was found to be significantly different from bonding in the aryloxide systems.

Synthesis of group 1 metal 2,6-diphenylphenoxide complexes [M(OC6H3Ph2-2,6)] (M = Li, Na, K, Rb, Cs) and structures of the solvent-free complexes [Rb(OC6H3Ph2-2,6)]x and [Cs(OC6H3Ph2-2,6)x: one-dimensional extended arrays of metal aryloxides.

Reaction of 2,6-diphenylphenol (HOC(6)H(3)Ph(2)-2,6) with (n)BuLi, NaH, KH, or Rb or Cs metal in benzene gives the solvent-free complexes [M(OAr)]x in excellent yield. The complex [Rb(OC(6)H(3)Ph(2)-2,6)](x)() exhibits a ladderlike structure in the solid state with triply bridging oxygen atoms and Rb-O distances of 2.743(3), 2.

Facile resolution of constrained geometry indenyl-phenoxide ligation.

The 2-(inden-3-yl)phenoxide ligand can be resolved at both tetrahedral and octahedral Group 4 metal centers using chiral binaphthoxide ligands.

Novel, stereoselective tricyclization of a dienyne by titanium aryloxide centers.

Titanium centers supported by aryloxide ligation mediate the tricyclization of a dienyne via intramolecular insertion of an olefin into the titanium-vinyl bond of a titanacyclopent-2-ene.

Structural Distortions in Six-Coordinate Adducts of Niobium(V) and Tantalum(V).

The mixed chloro-aryloxide compounds [M(OC(6)H(3)Pr(i)(2)-2,6)(2)Cl(3)](2) (M = Nb (1a), Ta (1b); both structurally characterized) and [M(OC(6)H(3)Pr(i)(2)-2,6)(3)Cl(2)] (M = Nb (2a), Ta (2b)) react with pyridine (py) and PMe(2)Ph to produce a series of adducts cis-mer-[MCl(3)(OC(6)H(3)Pr(i)(2)-2,6)(2)(L)] (M, L: Nb, py (3a); Ta, py (3b); Nb, PMe(2)Ph (4a); Ta, PMe(2)Ph (4b)) and trans-mer-[MCl(2)(OC(6)H(3)Pr(i)(2)-2,6)(3)(L)] (M, L: Nb, py (5); Nb, PMe(2)Ph (6a); Ta, PMe(2)Ph (6b)). The assigned geometric arrangement of ligands is based upon (1)H NMR studies and single-crystal X-ray diffraction analyses of 3a, 3b, 4, 6a, and 6b. The salt complex [HPMe(2)Ph](+)[mer-NbCl(3)(OC(6)H(3)Pr(i)(2)-2,6)(3)](-) (7) has also been isolated and structurally characterized.