The gas-phase (electron diffraction) and solid-state (X-ray) structures of W(NBut)2(NHBut)2 (1) have been determined. In the gas phase, 1 adopts both C1 and C2 conformations in a 69:31 ratio. The solid-state structure is disordered over two equal sites, both showing approximate C2 conformation as in the gas phase; the imido and amido centers are, however, clearly distinguished. Compound 1 has been used to synthesize novel heterobimetallic derivatives W(NBut)4[Rh(COD)]2 (3) and W(NBut)4[Pd(eta3-C3H5)]2 (4) via the dilithiated intermediate Li2[W(NBut)4] (2). In both cases, the [W(NBut)4] moiety bridges the two organometallic fragments. Reaction of 1 with Me2Zn has produced [Me(tBuN)W(mu-NBut)2ZnMe(NH2But)] (5). The structures of 3, 4, and 5 have been determined. Thermal decomposition of 4 under an autogenerated pressure at 700 degrees C has formed the hitherto uncharacterized bimetallic alloy WPd2.

A series of M 2 W 2 (O) 2 (acac) 2 (OMe) 10 [M = Co (1), Ni(2), Mg (3), Zn (4)] have been synthesised and structurally characterised by X-ray crystallography. All the compounds share common structural features which are identical to the analogous molybdenum species, with four edge-sharing octahedra situated in the same plane, and incorporating two  3-bridging and four  2-bridging methoxide groups. The divalent metal M and tungsten have both octahedral coordination environments with six oxygen atoms. The structure of Na[Zn(acac) 3 ] (6), a by-product of a failed synthesis of 4, is also reported, and is a linear polymer in which [Zn(acac) 3 ] anions use all six oxygen atoms to link sodium cations either side of the anion. Thermal decomposition of representative samples (1, 3) shows them to be single-source precursors for metal tungstates MWO 4. When the decomposition is carried out under an autogenerated pressure (RAPET) at 700 o C 1 forms CoWO 4 nanoparticles, along with WOx-filled carbon nanotubes and amorphous carbon, while 3 forms MgWO 4 nanoparticles and rods, though the latter lack a carbon shell and are much shorter in length.

The tungsten aminoalkoxides W(O)(OPr(i))(3)L [L = dmae, OCH(2)CH(2)NMe(2) (1); bdmap, OCH(CH(2)NMe(2))(2) (2); tdmap, OC(CH(2)NMe(2))(3) (3)] have been synthesised. Controlled hydrolysis of 1-3 has allowed isolation of W(4)O(4)(μ-O)(6)(dmae)(4) (4), W(4)O(4)(μ-O)(4)(OPr(i))(4)(bdmap)(4) (5), W(6)O(6)(μ-O)(9)(tdmap)(6) (6), W(4)O(4)(μ-O)(6)(tdmap)(4) (7), W(4)O(4)(μ-O)(6)(tdmap)(4)·4H(2)O (7a), all of which have been characterised by X-ray crystallography. 4, 7, 7a each embody a W(4)O(6) core with adamantane structure, 5 incorporates a folded W(4)O(4) square and 6 has a trigonal prismatic W(6)O(9) at its heart. 7 decomposes in air at to give orthorhombic WO(3), while 1-3 decomposed under an autogenerated pressure (Reaction under Autogenic Pressure at Elevated Temperatures, RAPET) to form mixtures of carbon-coated WO(x) needles and carbon spherules.

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