| Transition metals-catalyzed Suzuki-Miyaura reaction is an importantmethod for the formation of the carbon-carbon bonds in organic synthesis.Recently, considerable efforts were devoted to optimize the reactionconditions for the palladium Suzuki-Miyaura reaction by the chemistries.The contents of thisdissertation mainly discussed the use of amines asligands for the palladium-catalyzed the Suzuki-Miyaura reactions.Six- to eight-membered-ring carbocycles are common structuralunits of biologically important natural products. Although many methodshave been developed for the synthesis of these carbocyclic compounds,transition metal catalyzed cyclization is considered to be one of the mosteffective strategies. Herein, the contents of this dissertation also discussedPdCl2(MeCN)2/CuCl2/PEG-400-catalyzed intramolecular cyclizationreaction of unactived alkene.1. The scope and limitations of the Pd(OAc)2/DABCO(1,4-diaza-bicyclo[2.2.2]octane)-catalyzed Suzuki-Miyauracross-coupling reactions have been demonstrated. The results showedthat effect of solvent has a fundamental influence on the reaction. In thepresence of Pd(OAc)2 and DABCO, both aryl bromides and aryl chlorides,all work well with arylboronic acids to form biaryls, heteroaryl-aryls andbiheteroaryls in moderate to excellent yields using DMF as the solvent. In addition, the reactions of aryl bromides were conducted under relativelymild conditions.2. The combination of Pd(OAc)2 and N,N'-dimethyl etheneyl diaminewas observed as an efficient catalytic system for the Suzukicross-coupling reaction. In the presence of Pd(OAc)2 and N,N′-dimethyletheneyl diamine, a number of benzyl chlorides and acetyl chlorides werecoupled efficiently with various arylboronic acid in good to excellentyields.3. PEG-400 [poly(ethylene glycol-400)] was found as an effectivemedium for the PdCl2(MeCN)2-catalyzed intramolecular cyclizationreaction of alkenylβ-keto esters and amides. We found accidentally thatno additives such as Me3SiCl and Ln(OTf)3 were required for thecomplete conversion of alkenylβ-keto esters in PEG-400. The resultsalso showed that CuCl2 could promote the reaction. In the presence ofPdCl2(MeCN)2, CuCl2, and PEG-400, various alkenylβ-keto esters andamides underwent selective cyclization reaction to give good to excellentyields of the desired six-membered-ring carbocycles. Furthermore, thePdCl2(MeCN)2/CuCl2/PEG-400 system could be recycled and reused fivetimes without any loss of catalytic activity.
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