Thesis (Ph.D.)--University of Delaware, 2007. / Principal faculty advisors: Jingguang G. Chen and Raul F. Lobo, Dept. of Chemical Engineering. Includes bibliographical references.

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 121-127). Also available via the Internet.

Thesis (Ph. D.)--University of Hong Kong, 1994. / Includes bibliographical references (leaves 242-250).

Thesis (PH. D.)--Michigan State University. Chemistry, 2008. / Title from PDF t.p. (viewed on Sept. 2, 2009) Includes bibliographical references (p. 175-173). Also issued in print.

Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (leaves 187-190). Also available in print.

Thesis (M.Ch.E.)--University of Delaware, 2005. / Principal faculty advisors: Jingguang Chen, Raul F. Lobo, Dept. of Chemical Engineering. Includes bibliographical references.

Transition metal-catalysed cross coupling chemistry is a valuable tool for synthetic organic chemistry, enabling the preparation of compounds of great interest. The catalytic metal of choice is usually palladium, which generally offer better performances in term of catalytic activity and easy handling. On the other hand, the use of nickel in this class of reactions is gaining attention, as it would provide more economically and environmentally sustainable processes. Deprotonative cross couplings are a subgroup of these reactions, in which the nucleophile is generated in situ by direct deprotonation of a (relatively) acidic C–H bond, for example those of an enolizable ketone or an imine. The reaction products often represent intermediates towards more complex molecular architectures, by virtue of the well-known carbonyl chemistry. The development of a Pd-catalysed methodology for the prototypical deprotonative coupling, the a-arylation of ketones, is reported in this thesis. It requires significantly lower catalyst loadings compared to previous reports, and displays good tolerance towards functionalised substrates. A related protocol for the intramolecular a-arylation of imines towards indoles was subsequently disclosed: as it requires low catalyst loadings and displays good scalability and simple setup, this methodology is a promising hit for industrial applications. The parallel development of nickel-catalysed protocols afforded an efficient method for the a-arylation of ketones, using chloroarenes as electrophile for the first time in the literature. The method was further optimised for the synthesis of an intermediate towards a commercial medicinally active compound. Building up on these findings, the first nickel-catalysed protocol for the deprotonative arylation of benzylaminederived imines was also developed. Last, the first aqueous palladium-catalysed protocol for the a-arylation of ketones was investigated. The method proved flexible, showing excellent functional group tolerance: compounds containing base-sensitive functional groups, halogenated small-molecule drugs, and Boc-protected amino acids were all suitable substrates.

M.Sc. / The objective of the project described in this dissertation was the preparation of a range of bulky electron-rich phosphine ligands making use of the directed ortho metallation (DoM) methodology developed in our labs. These ligands would then be employed in the Suzuki and Heck reactions of aryl bromides and aryl chlorides. A range of phosphinic amides were synthesised with various structural differences. These phosphinic amides all showed high activity in the DoM reaction when using TMSCl and MeI as electrophiles, by successfully incorporating TMS and Me groups in the ortho-positions of these phosphinic amide systems. A phosphonic amide was also synthesised and used in the DoM reaction, and also successfully incorporated TMS and Me in the ortho-position of this system. The success of these reactions was encouraging and provided a route to incorporate a phosphine on the ortho-position of these phosphinic amide and phosphonic amide systems by using a range of phosphine electrophiles Ar2PCl. The route was versatile and various electrophiles were used to prepare phosphine ligands with varying electronic and steric properties. These electrophiles were prepared from PCl3 and the corresponding Grignard reagent. Vaska-type complexes and phosphine selenium coupling constants were used to determine the electronic and stereo-electronic characteristics of the prepared ligands. The phosphine ligands prepared in this project making use of our DoM methodology were tested in the Suzuki cross-coupling reactions and Heck arylation reactions of aryl bromides and aryl chlorides and showed good reactivity with most of the substrates used. An advantage of the ligands prepared is that these ligands are oxidatively and hydrolytically stable

M.Sc. (Chemistry) / The work in this thesis describes some catalytic reactions of aluminium triflate. This Lewis acid has been shown to be of great value in the catalysis of several types of organic transformations. These include but are not limited to the alcoholysis and aminolysis of epoxides, uses in methoxycarbonylation catalysis and in esterification reactions. Therefore, aluminium triflate holds promise for application in both the bulk and fine chemistry industries. Aluminium triflate has received little interest compared to some other, more costly triflates such the lanthanide triflates. Oxetanes were used in various catalysis experiments during this study, yet few are commercially available. Therefore, various synthetic approaches to the synthesis of 2-phenyl-oxetane were explored. There were many failed attempts, but the preparation was eventually successful using a sulfur ylide route with good yield. The next part of this thesis explores the boundaries of ring-opening reactions of oxetanes. Lewis acid ring-opening of oxetanes has been neglected compared to that of epoxides, likely because it is a more difficult undertaking. Yet, alcoholysis reactions showed good yields with a variety of different alcohol substrates. Some of the alcohols contained functionality which could provide access to further modification. Furthermore, the aminolysis and thiolysis of oxetanes were explored, essentially without success. However, with an activated oxetane it was shown that oxetanes could be opened with good yield under mild conditions with amines and thiols...

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