Palladium-catalyzed oxidative difunctionalization of alkenes: New reactivity and new mechanisms

Oxidative am nations of alkenes such as haloaminations and diaminations are of special importance in synthetic chemistry. These reactions allow for the transformation of the ubiquitous carbon-carbon double bond into motifs with a range of applications. The nitrogen-containing heterocycles formed from these reactions are an important class of molecules containing a rich variety of biological activity. In this dissertation, development of new palladium-catalyzed haloamination and diamination reactions are disclosed. A detailed mechanistic study of this diamination is also presented.;A palladium-catalyzed chloroamination of protected aminoalkenes was developed using N-chlorosuccinimide (NCS) as an oxidant and source of Cl. This reaction generally shows high regioselectivity for exo -cyclization and works well with a number of different amine protecting groups. The chloride of the resulting products can be readily displaced by a number of nucleophiles to form new carbon-heteroatom or carbon-carbon bonds. Bromo- and iodoamination reactions were also successfully developed using NBS and NIS respectively.;In an attempt to develop a fluoroamination methodology using N-fluorobenzenesulfonimide (NFBS), a novel diamination product incorporating benzenesulfonimide was observed. Diamination can be performed to cyclize aminoalkenes with amide, carbamate, and urea-protected nitrogen. The resulting diamination products can be fully or partially deprotected readily. Additionally, oxygen nucleophiles and arenes can be incorporated to form oxyamination and carboamination products using this methodology.;The mechanism of NFBS diamination was studied and was found to go through an anti-aminopalladation followed by direct nucleophilic attack by benzenesulfonimide on the Pd-C bond. These studies led to the first 2-aminoalkylpalladium complex to be isolated and fully characterized.