Zincative Functionalization of C-H Bonds Using Lithium Amide Zincate Bases
Katie Bitting, Ph.D. candidate
Qiu Wang, advisor
Tuesday, July 10, 2018 - 10:00am to 11:00am
Location: French Family Science Center 3232
Avery, Meg

Direct carbon-hydrogen bond functionalization is a highly desirable transformation, as C-H bonds are plentiful in feedstock chemicals and the direct introduction of valuable functional groups improves atom economy and efficiency. However, the field of  C-H functionalization still has many challenges, including regioselectivity, directing group limitations, and often harsh reaction conditions with toxic and rare transition metal catalysts. In order to address these limitations, this dissertation focuses on the development of lithium zincate bases for the deprotonative zincation and functionalization of C-H bonds. Several lithium amide zincate bases have been developed and explored for the regioselective ortho zincation of arenes and heteroarenes, and alpha zincation of carbonyl derivatives. Utilizing this deprotonative zincation strategy, direct C-H amination of a wide scope of arenes and heteroarenes has been achieved by copper-catalyzed electrophilic amination with O-benzoyl hydroxylamines. Additionally, aryl and heteraryl lithium zincates have been shown to undergo transition metal-free electrophilic silylation and borylation transformations, generating valuable synthetic intermediates. Lithium zincate bases can also readily deprotonate substituted and unactivated amides, and C-C bond forming reactions, including allylation of these amide enolates, have been explored.