Transition Metal-Catalyzed Cyclization And C-H Activation And Asymmetric Hydrogenation

The present thesis aims at describing the fundamental studies on transition metal-catalyzed cyclization and C-H activation and asymmetric hydrogenation reactions. It mainly consists of the following four parts:The review introduced the more recent progress in nickel-catalyzed reactions in organic synthesis, and the fundamental mechanism was summarized in detail. And we present some nickel-catalyzed cross-coupling reactions, and nickel-catalyzed reactions of alkenes, alkynes, allylic and propargylic compounds. Finally, we descried a detailed description a very nice advance of nickel(II)-catalyzed carboannulation reactions. In the presence of Ni3(PO4)2·8H2O catalyst, the propargylic compounds possesses a tune carbon nucleophilic center in close proximity to the propargylic moiety are used as substrates. And highly substituted indene derivatives including allene or ester group are readily prepared in moderate to excellent yields under very mild reaction conditions in air.The review introduced the more recent progress in Pd(0)-catalyzed tandem cyclization reactions in organic synthesis. According to the reaction processes, we classified them in two types involve the transformations with single or double nucleophiles. Finally, we descried a novel and convenient Pd(0)-catalyzed carboannulation with propargylic compounds bearing a carbonyl group with various amines for the synthesis of highly substituted aromatic amine derivatives in a one-pot operation. Moreover, the high regioand chemoselectivity makes this unprecedented transformation attractive in organic synthesis.The review introduced the more recent progress in Pd-catalyzed C-H activation/functionalization in organic synthesis. In view of mechanism, two hypothesis were proposed for this transformation. Then we present some Pd-catalyzed C-H activation reactions leading to C-C, C-N, C-S, C-X and C-O bond formation utilizing a monodentate system as directing functional groups. Finally, we descried a novel palladium-catalyzed aryl C-H bonds activation/acetoxylation reaction utilizing a bidentate system. This transformation has been applied to a wide array of pyridine and 8-aminoquinoline derivatives and it exhibits excellent functional group tolerance. This kind of bidentate system has large potential for the exploration of new reactions that have not been achieved by general monodentate-assisted systems.The review introduced the more recent progress and challenges in transition metal-catalyzed asymmetric hydrogenation in organic synthesis. Then we present some transition metal-catalyzed asymmetric hydrogenations of aromatic compounds including oxygen/nitrogen atom. Finally, we described an efficient enantioselective hydrogenation of a wide range of functionalized quinoline derivatives using the iridium-(S)-C3*-TunePhos catalyst. This method provided an efficient access to a variety of optically active tetrahydroquinolines with good to excellent enantioselectivities (up to 93% ee). Furthermore, attempts on the asymmetric hydrogenation of quinoline N-oxide are also discussed.