Synthesis And Properties Of Iron, Cobalt And Nickel Complexes Containing Sulfur Ligands

Metal hydrido complexes are of great importance in the areas of industrial production,drug synthesis,experimental catalysis due to it's special constructions.Generally speaking,they are postulated as key intermediates in a variety of chemical reactions.Last few years,noble metals had been deeply reported in the area of catalysis because their compounds have good activities.However,because of their highly price,environmental harmful and toxicity,more and more scientists hope to find cheap metals to replace it.Iron,cobalt and nickel as inexpensive transition metals have shown many significant advantages for its cheap,environment-friendly,biological importance,and abundant in the nature.Many groups spend much more energy study these metals,and experimental reactions prove that iron,cobalt and nickel are better than noble metals in some chemical reactions.For years,noble metals?Ir,Re,Ru,Mo,Au etc.?are preferred for their excellent chemo-selectivity and chemical activity.But iron,cobalt and nickel also have special structure and nature,moreover they have obtained good achievement in some catalytic reactions of unsaturated compounds.The study of pincer ligand is extensive and depth,relative to pincer ligand.mono-and bidentate ligands are easier to prepare,and metal complexes seem to be more lively.Complexes formed by iron,cobalt and nickel have some special chemical properties because of mono-and bidentate ligand.This dissertation is mainly divided into five sections.1.Synthesis and properties of iron hydrido complexes through S-H bond activation by Fe?PMe₃?₄A series of ligands L1-L5 containing S-H bond were synthesized.Some metal hydrido complexes 1-4,9 were prepared by the reaction of L1 1 L5 with Fe?PMe₃?₄.Metal carbonyl complexes were obtained through the reaction of 1-4,9 with CO.These complexes were full detected by spectral analysis and some of them were determined by X-Ray.Complexes 1-4 showed good catalytic performance in hydrosilylation of carbonyl compounds and dehydration of primary amides.2.Synthesis and properties of iron hydrido complexes by reactions of Fe?PMe₃?₄ with[P,S]-chelating ligandsA series of ligands L6-L10 containing[P,S]-chelating were synthesized.Some metal hydrido complexes 11-14,19 were prepared by the reaction of L6-L10 with Fe?PMe₃?₄.Metal carbonyl complexes were obtained through the reaction of 12-14,19 with CO.We also got complexes 18,21 to study the property of metal hydrides.These complexes were full detected by spectral analysis and some of them were determined by X-Ray.Complexes 11-14 showed good catalytic performance in hydrosilylation of carbonyl compounds.3.Synthesis and properties of nickel hydrido complexes by reactions of Ni?PMe₃?₄ with[P,S]-chelating ligandsActivation of S-H bonds in L7-L10 by Ni?PMe₃?₄ to obtain nickel hydrido complexes 22-24,41.Novel vinylnickel and nickelacyclopropane complexes?25-36?were obtained by insertion of alkynes into Ni-H bonds.Complexes 37-40 were gained by complexes 22-24 with dppp and phenylallene.DFT calculations verified the rationality of structures of complexes 29 and 32.These complexes were full detected by spectral analysis and some of them were determined by X-Ray.4.Synthesis and properties of cobalt complexes by reactions of L7-L9 with[P,S]-chelating ligandsActivation of S-H bonds in L7-L10 by Co?PMe₃?₄,CoMe?PMe₃?₄,CoMe2?PMe₃?₃ and CoCl?PMe₃?₃ to obtain Co???complexes 42-44,bis-chelated complexes 48-50,54,55 and cobalt chloride complexes 45-47.Cobalt carbonyl complexes 51-53 were gained by the reaction of 42-44 with CO.These complexes were full detected by spectral analysis and some of them were determined by X-Ray.5.Highly regioselective addition of thiophenol to terminal allenes catalyzed by Ni?PMe₃?₄A new catalytic system of highly regioselective addition of thiophenol to terminal allenes has been performed using easily available nickel complexes.The moderate yields were obtained and the highly atom-economic was realized through studying inexpensive nickel complexes under mild conditions.The mechanism was investigated and the intermediate was obtained.The molecular structure of product were determined by X-Ray.