New Approaches to Catalysis: Dual Nucleophilic/Transition Metal Catalysis and Bimetallic Cu Catalysts for Oxidative Functionalizations

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Catalysis plays an enormous role in the synthesis and production of nearly all chemicals. Close to 10 trillion dollars of gross world product are directly reliant upon some type of catalytic process. Studies directed towards the development of new homogeneous catalytic species and reaction pathways have made a major impact on virtually all areas of chemistry and its ancillary fields (biology, materials science, drug discovery, etc.) However, despite the remarkable advances made in the area of homogeneous catalysis, many conceptually simple and potentially revolutionary chemical transformations remain out of reach. It is the overarching goal of our research group to develop new catalysts and chemical reactivity to provide solutions to challenges in modern chemistry.In order to develop new and useful reactivity, we have identified two core areas of study we intend to focus upon. One area centralizes around the hypothesis that N-heterocyclic carbene (NHC) activation of electrophiles can be merged with simultaneous substrate activation by late transition metals, such as Au, Pd, Ru, and Ir. We will use this powerful principle to develop a number of important chemical transformations. Such examples include: 1. The NHC/transition metal catalyzed allylic functionalization of aldehydes; 2. The NHC/Au-catalyzed intermolecular hydroacylation of simple alkenes; and 3. The development of "programmable" Benzoin condensation reactions via NHC activation and transition metal catalyzed dehydrogenation/hydrogen transfer. In each case, exquisite control over chemo-, regio-, and enantioselectivity can be achieved by proper selection of catalyst components. A second area of research we will pursue is the concept of bimolecularity as a strategy to enable improved or novel Cu-catalyzed oxidative functionalizations. We will develop two branches of bimetallic Cu-containing catalysts: one aimed to promote organometallic oxidase activity and allow, for example, the oxidative coupling of arenes and ketones; and a second aimed at mimicking the reactivity of dicopper hydroxylating enzymes to enable selective sp3 C-H bond oxidative hetero-functionalizations. The concepts and the knowledge we develop will allow for new reactivity with simple and abundant substrates, such as alkenes, aldehydes, alcohols, and C-H bonds, all of which will have significant impact on chemical synthesis.