Synthesis and Electronic Structure of Group 9 Metal Clusters with Novel Framework

点击翻译按钮获取中文摘要

This project explores the novel cluster compounds in which the frontier orbital in the group 9 metal framework delocalizes onto the ligands. We also aim to control the shape of the frontier orbital and the redox potential together.( 1 ) Cobalt-rhodium mixed metal trinuclear clusters were synthesized. The redox potential of them indicated that the HOMO-LUMO gap of them were large in the rhodium rich clusters.( 2 ) The cationic radical salt of [ Co_3Cp_3( μ_3-CPh )_2 ] was synthesized and determined its X-ray structure. Its HOMO was determined as outof-plane orbital which has appreciable electron density on the capping carbon atoms by using comparison of Xray data and ^1H-NMR paramagnetic shift.( 3 ) Tricobalt clusters with halide-bridge [ Co_3Cp_3( μ_3-CPh )_2(μ-X ) ] were synthesized. The formation of the clusters were via oxidation of the intermediate which was constructed from the cation of the cobalt complex and halide ion.( 4 ) Bis( μ-acetato ) dichlorodicarbonyldiiridium ( II ) complexes with group 15 compounds as the axial ligands, [ Ir_2( μ-O_2CMe )_2Cl_2( CO )_2L_2 ] ( L = PPh_3, PCy3 , P( OPh )_3, AsPh_3, SbPh_3 ) were synthesized. The Ir-Ir distances were longer than those of acetonitrile compounds. The complexes had a chemically reversible one-electron oxidation wave of which E1/2 values were 0.21 V for PCy3 complex. The ESR results indicatelhat their SOMO is the ^σIrIr orbital with ^σIrP^* or ^σIrAs^* character.( 5 ) tetranuclear rhodium complex [ Rh_4( O_2CPr)_4Cl_4( CH_3CN )_4 ] catalyzed hydrogenation of olefin compounds.( 6 ) A novel iridium( II ) dimer complexes with thiocarboxylato bridge were synthesized