| Transition metal catalysts have high selectivity in synthetic chemistry.It has recently been the most active field in organic synthesis chemistry.Transition metal hydrido compounds are important catalysts in olefin polymerization and hydroformylation reaction.Metal thiolate complexes are involved in fundamental catalytic(e.g,hydrodesulfurization)and biological(e.g,iron-sulfur proteins)process.Transition-metal cluster molecules continues to supply efficient syntheses that do not succeed with mononuclear catalysts.Much attention has been paid to the investigation of a variety of binuclear metal complexes,especially those ligated by sulfur donor atoms,because of their resemblance to the active sites of some metalloproteins,which mediate redox reactions and electron transfer in biological systems.In this paper reactions between cobalt compounds supported by trimethylphosphane (Co(PMe3)4Me,Co(PMe3)4,Co(PMe3)3Cl)and sulfur-containing ligands are described. The new sulfur-containing hydridocobalt compounds and new sulfur-containing dinuclear cobalt compounds have been synthesized.Their reaction properties are also been studied.Synthesis of new dinuclear hydridocobalt complexes supported by trimethylphosphane has been attempted primarily from the reactions between cobalt compounds(Co(PMe3)4Me,Co(PMe3)3Cl,Co(PMe3)3Me3)and dinuclear ligands (bis-shiffobase,6,6'-dihydroxy-3,3'-methylene-dibenzaldehyde,6,6'-dihydroxy-5,5'-dimethoxy-3,3'-methylenedibenzaldehyde).All the new compounds have been confirmed by X-ray crystal diffraction,IR,NMR or elementary analysis.The details of the work include the following four aspects;1.Synthesis of new sulfur-containing hydridocobalt complexesThe new hydridocobalt(Ⅲ)complex HCo(SPh)2(PMe3)3(1)has been prepared by the reaction of PhSH with Co(PMe3)3Cl,Co(PMe3)4 or Co(PMe3)4Me.But new dinuclear cobalt complex Co2(SPh)2(PMe3)4(2)is also obtained from the reaction of PhSH with Co(PMe3)4Me at the same time.2-mercaptobenzaldehyde and 5-methyl-2-mercaptobenzaldehyde react with Co(PMe3)4Me respectively yielding the sulfur-containing hydridocobalt(Ⅲ)compounds 3,4.The crystal structures of compounds 1,2 and 3 have been determined by X-ray diffraction.2.Porperties of sulfur-containing hydridocobalt complexesReactions between hydridocobalt(Ⅲ)complex 1 and CH3I,phenylethyne and trimethylsiliconacetylene have been studied respectively.The new compound CoI2(PMe3)3(5)is obtained from the reaction between complex 1 and CH3I.The new compound Co(PhS)2(PMe3)3(6)is obtained from the reactions between complex 1 and phenylethyne or trimethylsiliconacetylene.The possible reaction mechanisms of all the reactions have been proposed.The crystal structures of compounds 5 and 6 have been determined by X-ray diffraction.3.Synthesis of new dinuclear hydridocobalt complexesDinuclear cobalt complex Co2(SPh)2(PMe3)4(2)is obtained from the reaction between PhSH and Co(PMe3)4Me.Either Co(PMe3)4 or Co(PMe3)4Me reacts with 1,2-benzenedithiol affording the dinuclear compound Co2{μ2-S,μ3-S][C6H4(SS)]}2-(PMe3)4(7).Another new dinuclear cobalt complex Co2{[μ2-S,μ3-NH]-[C6H4(NH)S]}2(PMe3)4(8)was obtained from the reaction between 2-aminobenzenethiol and Co(PMe3)4Me.Carbon monoxide reactions of the dinuclear cobalt complexes 2,7 and 8 yield the compounds 9,10 and 11 respectively.The possible reaction mechanisms of the reactions have been discussed.The crystal structures of compounds 7,8 and 9 have been determined by X-ray diffraction.Co2{[S,μ2-N][C6H4NS]}(CO)2(PMe3)4(12)was obtained from the reaction between 2-aminobenzenethiol and CoCl(CO)(PMe3)3.The crystal structures of compounds12 has been determined by X-ray diffraction.4.The attempts to synthesize new dinuclear hydridocobalt complexesThe new dinuclear ligand 6,6'-dihydroxy-5,5'-dimethoxy-3,3'-methylenedibenzal-dehyde(15)has been synthesized.The crystal structure of compound 15 has been determined by X-ray diffraction.Synthesis of new dinuclear hydridocobalt complexes supported by trimethyl- phosphane from reactions between cobalt compounds(Co(PMe3)4Me,Co(PMe3)3Cl, Co(PMe3)3Me3)and dinuclear ligands(bis-shiffbase,6,6'-dihydroxy-3,3'-methylene-dibenzaldehyde,6,6'-dihydroxy-5,5'-dimethoxy-3,3'-methylenedibenzaldehyde)have been attempted primarily.
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