Transition Metals Catalyzed Organic Transformations, Oxidative Cycloadditions, Cyclizations and Dimeric Cyclizations on Diverse Enynes

• Main Authors: SATISH MADHAV GHORPADE, 沙提斯
• Other Authors: 劉瑞雄
• Format: Others
• Language: en_US
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/10262012132558338430

博士 === 國立清華大學 === 化學系 === 103 === ABSTRACT This dissertation describes development of new synthetic organic transformations by using gold and copper salts. The use of these soft alkynophilic metals enables mild, diastereoselective and efficient transformations of a variety of readily available substrates to wide range of synthetically useful and biologically important N, O containing heterocyclic and carbocyclic products. For better understanding the thesis is divided into four chapters. The first chapter deals with the Gold-catalyzed oxidative cyclizations of cis-3-En-1-ynes to form cyclopentenone derivatives. The title reaction for synthesizing cyclopentenone derivatives utilizes a gold complex and 8-methylquinoline oxide as the catalyst system. The value of such reactions is reflected by their applicability to a broad range of benzene- and nonbenzene-derived substrates, thus giving various indanone and cyclopentenone derivatives, respectively. Such products are not attainable using diazocarbonyl reagents, as the gold carbenoids tend to react with C-H bonds. The second chapter deals with the gold-catalyzed oxidative cyclizations of 1,4-enynes were used to study the γ-effect on the Wagner–Meerwein rearrangement. Both experimental and theoretical work disclose that a gold substituent in the γ-position can direct a stereospecific 1,2 shift of the anti-β-substituent regardless of its intrinsic properties. The third chapter describes gold-catalyzed reactions of 3,5- and 3,6-dienynes with 8-alkyl- quinoline oxides results in an oxidative cycloaddition with high stereospecificity, this process involves a catalytic activation of a quinoline framework. The reaction mechanism involves the intermediacy of α-carbonyl pyridinium ylides (I) in a concerted [3+2]-cycloaddition with a tethered alkene. The fourth chapter presents the work aim at one-step construction of complex and important molecular frameworks via Cu-catalyzed oxidations of cheap tertiary amines. Cu-catalyzed aerobic oxidations of N-hydroxyaminopropenes to form C2-symmetric N- and O-functionalized cyclohexanes.