We are investigating the synthesis, characterization and reactivity of new inorganic and organometallic molecules and materials. New materials are characterized by a variety of physical methods including X-ray diffraction and NMR.
1. Organotransition Metal 糖心vlog官方入口. Organometallic chemistry is one of the most active areas of modern chemical research. Many of our target complexes are models for putative intermediates in industrially important reactions such as the conversion of synthesis gas (CO/H2) or acetylene to useful organic products. We are particularly interested in complexes of small, all-carbon ligands. The tungsten-catalyzed alkyne metathesis of [Ru(CCMe)(CO)2(Cp)] leads to either [(Cp)(CO)2Ru(碌-C)W(OCMe3)3] or [{Ru(CO) 2(Cp)}2(碌-CC)] (1), depending on reaction conditions. The ethynediyl (C2) ligand of 1 reacts with transition metal carbonyls to form heteronuclear bicarbide clusters such as [Fe2Ru2 (碌4-CC)(碌-CO)(CO)8(eta-C5H5)2] (2). The reaction of Na[Fe(CO)2(Cp)] with [C3Cl3][SbF6] produces a cyclo-C3 complex, [{Fe(CO)2(Cp)}3 (碌3-C3)][SbF6] (3).
We are also studying complexes of cumulated carbenes such as vinylidene (C=CH2) and allenylidene (C=C=CH2). For example, the reaction of acetylene with [RuCl(PMe2Ph)2(Cp)] leads to kinetically favored [Ru(eta2-HCCH)(PMe2Ph)2(Cp)]+ (4), which rearranges to its thermodynamically favored vinylidene isomer [Ru(C=CH2)(PMe2Ph)2(Cp)]+ (5) above 60oC.
Interactions of thiophenes with transition metals are important both in the hydrodesulfurization of fossil fuels and in the area of electrically conducting polythiophenes. We are especially interested in benzo[c]thiophene, which readily polymerizes to a conducting polymer with a small electronic band gap. We have prepared both sigma- and pi-bonded organometallic derivatives of benzo[c]thiophene, namely [Cr(eta6-C8H6S)(CO)3] (5) and [{Ru(CO)2(Cp)}2(碌2-C8H4S)] (6).
2. Fullerene 糖心vlog官方入口. The discovery of C60, C70, and larger cagelike molecular allotropes of carbon has revolutionized the study of this element. We are interested in several aspects of these new materials. A HPLC method developed in collaboration with Prof. Meier allows us to separate and purify significant quantities of fullerenes and their derivatives. The larger fullerenes C76, C78 and C84 were purified by HPLC and studied electrochemically. We are developing new fulleride salts with metal-complex cations.
3. Low-Dimensional Materials. In the intercalation process, guest molecules such as cobaltocene enter the space between the layers of inorganic hosts such as FeOCl and TaS2, generally with concomitant charge transfer. Intercalation modifies the physical properties of the host as well as the chemical properties of the guest. We are developing new intercalation compounds with organometallic guests.
