The development of new, improved methods for forming carbon–carbon and carbon–heteroatom bonds is the basic goal in synthetic organic chemistry. In the Lautens group, many recent advances have been made using late transition metals such as rhodium and palladium. One such research project involves the synthesis of indoles through tandem C–N and C–C coupling reactions using gem-dibromoolefin starting materials, and this area serves as a starting point for the research described. Chapter 1 describes a method by which the tandem use of gem-dibromoolefins can be halted to give intramolecular monocoupling reactions, maintaining one of the carbon–bromine bonds which can serve as a useful handle for further functionalization. The use of copper as a catalyst is key to this reaction, as it features a unique mechanism for carbon–heteroatom bond formation. Benzofurans and benzothiophenes can be prepared by this method. Chapter 2 describes the synthesis of 2-bromoindoles using an intramolecular Buchwald–Hartwig amination of gem-dibromoolefins. It is found that the products are more reactive towards palladium(0) than the starting material, and the use of a bulky phosphine ligand which facilitates reversible oxidative addition is required. This represents one of the first catalytic applications of this step in synthesis. Chapter 3 further explores the concept of reversible oxidative addition in a novel carbohalogenation reaction of alkenes. Aryl iodides tethered to alkenes are treated with a palladium(0) catalysts, which can undergo the basic steps of oxidative addition, carbopalladation, and novel sp2 carbon–iodine reductive elimination. This process is remarkably simple in concept, and is a waste-free, atom economically method for preparing new carbon–carbon bonds. Chapter 4 discusses various limitations to the carbohalogenation methodology, and seeks to overcome these problems. The use of aryl bromide starting materials can be accomplished by adding an iodide source to the reaction, allowing halide exchange of palladium(II) intermediates to occur. Intermolecular and asymmetric variants are also explored. Computational studies are discussed which reveal useful mechanistic details of the catalytic cycle, and this information is used in the development of novel phosphine ligands.

The synthesis and characterization of pyridinyl &alpha / -diimine Pd(II) complexes having a functionalized hydrocarbon attached to the imino nitrogen was performed. The catalytic activity of these complexes were then evaluated in the polymerization of ethylene and in the Heck coupling reaction of methyl acrylate with iodobenzene.<br /> <br /> Unconjugated &beta / -diimine complexes of palladium were also synthesized and their activities towards ethylene polymerization and the Heck coupling of methyl acrylate and iodobenzene also evaluated and compared to that of the &alpha / -diimine complexes. Three of the &alpha / -diimine complexes synthesized showed activity towards ethylene polymerization, these being the complexes bearing the allyl, styrene and phenol functionalities. &omega / -Carboxylato complexes which were also synthesized showed no activity towards ethylene polymerization.<br /> <br /> The polymer produced was found to be high density linear polyethylene with an average PDI of 2.54 with Mn values ranging between 3.42 and 6.90 x 10-5 and Mw values ranging between 6.05 and 17.6 x 10-5.<br /> <br /> The complexes bearing the allyl, styrene and phenol functionalities, as well as the &omega / -carboxylato complexes active in the Heck coupling reactions of methyl acrylate with iodobenzene. None of the unconjugated &beta / -diimine complexes prepared showed any activity towards ethylene polymerization even at high Al/Pd ratios. The activity of these complexes towards the Heck arylation reaction was comparable to that of the &alpha / -diimine complexes showing similar activities.

Zugl.: Karlsruhe, Univ., Diss., 2006

Proefschrift Universiteit van Amsterdam. / Met lit. opg. - Met samenvatting in het Nederlands.

Proefschrift Universiteit van Amsterdam. / Met lit. opg. - Met samenvatting in het Nederlands.

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

Universiẗat, Diss., 2006--Karlsruhe.

Diss. (sammanfattning) Uppsala : Univ., 2003. / Härtill 5 uppsatser.

Thesis (Ph. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains ix, 219 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 212-219).

Thesis (Ph. D.)--University of Sydney, 2008. / Title from title screen (viewed June 19, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Discipline of Biomedical Science, School of Medical Sciences, Faculty of Medicine. Degree awarded 2008; thesis submitted 2007. Includes bibliographical references. Also available in print form.