Project Summary
New methods for the formation of carbon-carbon bonds are always at the forefront of organic reaction
development. Of particular interest are those that require benign reagents, are atom-economical, and have low
energy input. The projects detailed herein aim to develop new umpolung carbon-carbon bond forming reactions
with visible-light mediated photocatalysis. Specifically, the projects seek to generate radical species by electron
transfer to ketone-containing functional groups. This reactivity will be enabled by photocatalytic electron transfer
either to or from an activated carbonyl species. Two specific goals will be approached: 1) Initial work will extend
preliminary experimental results that have shown that ketyl radicals can be generated by the combined activity
of photocatalysts and Lewis acids to enantioselective 1,4-additions with the use of chiral Lewis acids. 2) Electron
transfer from 1,3-dicarbonyls is proposed to generate electrophilic radicals for carbon-carbon bond formation
with nucleophiles. A variety of carbon-carbon bond forming reactions that involve 1,3-dicarbonyl radicals are
proposed, including hydro-, amido-, and dialkylation of alkenes. In total, these new catalytic processes will
provide highly efficient methods for the use of visible light to construct carbon-carbon bonds in complex and
biologically relevant molecular settings. The achievement of the designed umpolung reactivity of carbonyl-
containing compounds by single electron reduction or oxidation would broaden the scope of reactivity for these
widely available reagents. As a result, this proposal will contribute to the general toolbox of carbon-carbon bond
forming reactions with new methods that are able to simultaneously build molecular complexity and adjust
oxidation state. The projects are specifically tailored to be carried out by a research team composed entirely of
undergraduates and is therefore broken up into discrete individual projects. This proposal would enhance the
research training and outcomes of a diverse group of undergraduates pursuing careers in the biomedical
sciences.