Synthesis And Properties Of Novel Organonickel(Ⅱ)and Iron Hydride Complexes Coordinated With Sulphur Or Selenium Ligands

Nickel belong to the Ⅷ family of transition metals. Due to its relatively widely available, lower cost, lack of toxicity and environmental impact, it has attracted much more attention and become one of the wildly used metals. Phosphine ligands can be used as a kind of strong supporting ligands because of their fine coordination performance in coordination chemistry. Trimethylphosphine is one of the good phosphine ligand with the advantages of strong coordination ability, convenient preparation and good spectral performance. Thus, it can be coordinated with transition metals to form steady complexes. The nickel organic complexes coordinated with trimethylphosphine usually have highly reaction activity and selectivity.Metallothionein complexes are widespread biological electron transfer regulators. They exist in the basic catalytic processes (such as catalytic desulfurization) and biological processes (such as Fe-S protein). Therefore, the synthesis and properties of novel metal complexes containing sulphur ligands are becoming a hot research subject.This study is based on the previous research in our laboratory. We further used the complex3obtained from the reaction of NiMe2(PMe3)3with thiosalicylaldehyde to react with iodomethane. A new nickel(II) complex (thioetherphenyl)nickel(II)5was formed. We then discussed the formation mechanism. The reactions of organonickcl(Ⅱ) complex3with alkyl bromide such as bromoethane were also studied.The new complexes obtained were fully characterized and analyzed by IR,1H,31P NMR spectroscopy and melting point. The crystal structures of some complexes have been confirmed by X-ray diffraction. Iron belongs to the Ⅷ family of transition metals. Due to its relatively widely available, lower cost, lack of toxicity and environmental impact, it has attracted much more attention and become one of the wildly used metals. Phosphine ligands can be used as a kind of strong supporting ligands because of their fine coordination performance in coordination chemistry. Trimethylphosphine is one of the good phosphine ligand with the advantages of strong coordination ability, convenient preparation and good spectral performance. Thus, it can be coordinated with transition metals to form steady complexes. The iron organic complexes coordinated with trimethylphosphine usually have highly reaction activity and selectivity.Hydride compounds of transition metals have been investigated more widely as efficient catalyst in stoichiometric bond activations and catalytic transformations, especially those containing precious metals. Due to its excellent performance, iron is particularly attractive with comparable activity. Therefore, the study of hydride iron complexes has been a hotspot in the field of coordination chemistry for recent years.In this dissertation, new iron hydride complexes formed by oxidative addition of Se-H moieties were obtained through the reactions of Fe(PMe3)4with selenophenols. We then studied the reaction properties of the iron hydride complexes with CO and phenylacetylene. Meanwhile, new iron hydride complexes formed by thiophenol with Fe(PMe3)4was also synthesized. We comprehensively studied the catalytic application of the iron hydride complexes in hydrosilylation of aldehydes. The optimal condition for hydrosilylation of aldehydes is:complex6,7or13as catalyst (5%,1%,1%), triethoxysilane as hydrogen source, THF as solvent, temperature50℃and time2hours. We then discussed the catalytic mechanism.The new complexes obtained were fully characterized and analyzed by IR,1H,31P NMR spectroscopy and melting point. The crystal structures of some complexes have been confirmed by X-ray diffraction.