Abstract
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.