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The dimerization reaction of fluorinated alpha-halovinyl zinc and copper reagents and their thermal stability was explored. The structures of each of the isomeric members of butatrienes were characterized by X-ray crystallography. Dimerization of these vinyl carbenoids to butatrienes occurs when R is an aromatic C6H5 or C6F5 and R' is a perfluoroalkyl group CF3, C2F5, C3F7.

The d0 carbonyl complex Cp2Zr(CH)(Me)(6-ethlpyrid-2-yl))+ (compound 3) results from the carbonylation of the four-membered cationic azazirconacyle. A terminal CO ligand is evident for compound 3. A chelated structure in Zr(CH(Me)(6-ethylpyrid-2-yl) ligand is evident. In the case of azazirconacyle, back-bonding from only a single bonding orbital is possible.

A series of complexes [Tp.sup.R,RE]CoL, where [Tp.sup.R,RE] = hydrotris(3-R,5-RE-pyrazol-1-yl)borate (escorpionateE) anion (R = tert-butyl, RE = H, Me, 2E-thienyl (Tn), L = [Cl.sup.-], [NCS.sup.-], [NCO.sup.-], [N.sub.3.sup.-]), are studied by using electron absorption spectroscopy in the visible and near-infrared (near-IR) region and by high-frequency and ufield electron paramagnetic resonance (HFEPR). The electronic structure and bonding in pseudotetrahedral cobalt(II) complexes have increased the understanding of similar sites in metalloproteins, specifically cobalt-substituted zinc enzymes.

The synthesis and crystal structure of 2,5,8-triazido-s-heptazine, which is a rare example of a fully conjugated, polycyclic all carbon and nitrogen molecular compound is reported. The large numbers of nitrogen lone pairs present in 2,5,8-triazido-s-heptazine make it attractive as a component in a supramolecular metal coordination framework.

Propynylidene 1 (HCCCH) is the simplest alkynylcarbene that, along with abundant interstellar cyclopropenylidene 2 and propadienylidene 3 has attracted substantial interest. The propynylidene can be generated as an organodimetallic ligand in solution by double C-H activation of allene and it can adopt a curved structure.

Novel routes to W6Cl12(super 8) and crystalline, reactive (WCl4)(subscript x) from reduction of WCl6 with Hg, Sb or Bi with respect to trivalent tungsten chlorides were described. Tungsten chloride is considered to have an octahedral hexatungsten structure based on powder X-ray diffraction. Two new isostructural monocapped perchlorotritungstates, the first discrete group 6 trinuclear M3(mu3-L)(mu-L)3L9 clusters with similar ligands, as well as evidence for a new chloride, W3Cl10 were presented.

The alkane elimination reaction between Cp*MMe3 (Cp* = C5-Me5; M = Zr, Hf) and C2B9H13 forms a new metallocarborane complex, (C5Me5)(sub 2)(C2B9H11)(sub 2)Hf2Me2, that adopts an unusual unsymmetrical dinuclear framework bearing bridging dicarbollide ligands. The compound has Cp*(eta to the fifth power-C2B9H11)Hf+ and Cp*HfMe(super +)(sub 2) fragments bridged by a C2B9H(super 2-)(sub 11) group. The B-H bonds in these metallocarboranes are basic and the charge is distributed over the open face and the outside of the C2B9H(super 2-)(sub 11) cage.

Focuses on the preparation and characterization of a propynylidene organodimetallic complex arising from double C-H activation of an allene ligand. Single-crystal diffractometry revealing a micro-propynylidene coplanar with two Ta atoms; as of February 2003. medical device manufacturer; Reactivity of a new organometallic functional group.