Chu, John Chun Kit, authorRovis, Tomislav, advisorKennan, Alan, committee memberPrieto, Amy, committee memberKanatous, Shane, committee member2017-06-092017-06-092017http://hdl.handle.net/10217/181323This work first describes an enantioselective Zn-catalyzed [4+2] cycloaddition of 1-azadienes and nitro-alkenes for the synthesis of medicinally valuable piperidines. The detrimental coordination of 1-azadienes to the Zn catalysts undermines the stereochemical control of the reaction. Fortunately, a novel bisoxazoline ligand limits this undesired coordination and delivers high stereoselectivity. Mechanistic studies suggest the reaction proceeds via a stepwise mechanism in which aza-Michael addition is followed by cyclization. This proposed mechanism also explains the successful cycloaddition between two electron-deficient reaction partners. Secondly, amide-directed carbon-carbon bond formation at unactivated sp3 C-H bonds has been achieved using photoredox catalysis. The reaction features a hydrogen atom abstraction from the C-H bond to a nitrogen radical generated from the amidyl N-H bond, leading to formation of a carbon-centered radical. Trapping of the resulting alkyl radical with an electrophilic alkene gives the desired C-C bond formation. Experimental evidence supports the generation of the nitrogen radical through a stepwise deprotonation/oxidation event in a closed catalytic cycle. The potential to incorporate other functionalities in the C-H bonds, as well as g functionalization of carbonyl compounds, is disclosed.born digitaldoctoral dissertationsengCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.cycloadditionnitrogen-containing moleculeszinchydrogen atom transferC-H functionalizationradicalText