| Hydrogenation is one of the main methods to produce a large number of fine chemicals. Inthis thesis, a series of iridium-phosphine complexes [IrCl(COD)(MOTPP)], [IrCl(COD)(TFTPP)],[IrCl(COD)(BDPX)], [IrCl(COD)(BDNA)], [IrCl(COD)(BISBI)], [Ir(COD)(TFTPP)2]BF4,[Ir(COD)(BDPX)]BF4, [Ir(COD)(BDNA)]BF4, were synthesized and identified by 31p, 1H-NMRspectra and elemental analysis. These complexes were applied in the hydrogenation ofavermectin and quinoline. The water-soluble rhudium-phosphine complexes formed in situ wereemployed in hydrogenation of avermectin in aqueous-organic biphasic system.In order to understand the effect of electron factors and steric structures on thehydrogenations of avermectin and quinoline, another four complexes, [IrCl(COD)(TPP)],[IrCl(COD)(DPPM)], [IrCl(COD)(DPPE)], [IrCl(COD)(DPPP)] were prepared by the reportedmethod.The results show that iridium complexes beating electron-withdrawing phosphine exhibitshigher activity and lower selectivity for the hydrogenation of avermectin. Complex bearing TPPhas both high activity and high selectivity. On the one hand, the iridium complexes containingbulky phosphine is not favorable for this hydrogenation and a high content of by-productavermectin aglycon is formed. The reasonable explaination is bulky ligand is not favorable for COD dissociation in iridium complex and the active species is difficult to generate, so thehydrogenation is suppressed and the formation of byproduct is promoted. Furthermore, thereason for the formation of avermectin aglycon is related to the heterolytic split ofη2-H2 incomplex. The heterolytic split ofη2 -H2 in complex causes the formation of H+, which lead tothe split of C-O bond in avermetin. The cationic complexes exhibit low activities as they undergothe intermediate [Ir(ol)2L2]+ (ol=olefin) in the hydrogenation process.Besides being as an important model for the study of HDN process in petroleum industry, thehydrogenation of quinoline to form tetrahydroquinoline or its derivatives is important syntheticintermediate and structural unit of alkaloid. To direct hydrogenation of quinoline would be themost convenient route to obtain tetrahydroquinoline derivatives. In this thesis, we employediridium complexes mentioned above as catalysts for the hydrogenation of quinoline. The resultsshow that all these complexes are efficient catalysts for quinoline hydrogenation and they couldcompletely convert quinoline into 1,2,3,4-tetrahedroquinoline under mild conditions (85℃, 1MPa,5 hours) without any byproduction formation. The differences of catalytic activities of thesecomplexes provide us with the informations about the electronic and steric effects. The resultsindicate that complex bearing a electron-withdrawing ligand has higher activity and the stericeffect of ligand has little influence on quinoline hydrogenation. The results also show that thecationic complexes exhibit higher activities than their corresponding complexes containingchloride in the similar conditions..Employing [Ir(COD)(TPP)2]BF4 as a catalyst, we detect the intermediates in thehydrogenation process of quinoline by means of NMR insitu. The results show that quinolinereacts rapidly with [Ir(COD)(TPP)2]BF4, and then hydrogen is activated to produce intermediate[Ir(H)2(Q)2(PPh3)2]BF4 at room temperature. [Ir(H)2(Q)2(PPh3)2]BF4 was isolated and employedas catalyst to hydrogenate quinoline and its activity was almost the same as [Ir(COD)(TPP)2]BF4.The effect of react temperature on the hydrogenation was investigated and shows significantinfluence. Based on the research results, the rate-determining step is not the formation of[Ir(COD)(TPP)2]BF4 or [Ir(H)2(Q)2(PPh3)2]BF4 in the mechanism.The catalytic reaction in organic/aqueous two-phase catalytic system is one of the frontierfields in the "Green Chemistry". On the one hand, it has the merit of high activity and selectivityof homogeneously catalytic system. On the other hand, it solves the problem of the separation of catalyst from the production. A series water-soluble phosphine ligands were synthesized andcoordinated with [Rh(COD)Cl]2 in situ to catalyze the hydrogenation of avermectin. The effectsof ligand structure, reaction temperature, hydrogen pressure, the surfactant concentration, andinorganic salt were investigated.The results show that Rh-BISBIS exhibits the best activity. Thedouble long chain cationic surfactants could efficiently promote the hydrogenation. The volumeof solvent has a significant influence on this hydrogenation and appropriate ratio of toluene,ethanol, and H2O would cause the formation of bicontinous phase and improves the reactionconversion and selectivity. The additions of inorganic salt and organic base Et3N could stronglyinfluence the reaction activity and selectivity.
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