PROJECT SUMMARY/ABSTRACT Because a wide array of nitrogen-containing compounds exhibit bioactivity, the development of new methods for the formation of C–N bonds is a central challenge in synthetic organic chemistry. The discovery of catalysts for organic reactions is often desirable, since they can offer advantages from the standpoints of efficiency/economy. This proposal is directed at the discovery of new methods for metal-catalyzed C–N bond formation. Through the use of photoinduced copper catalysis via a radical pathway, we plan to expand the scope of N- alkylations well beyond that provided by SN2 reactions. These coupling reactions are anticipated to proceed under unusually mild conditions, to have broad applicability for the generation of diverse families of nitrogen- containing compounds, and to proceed with good stereoselectivity (when applicable). The research plan also describes mechanistic studies (e.g., isotopic labeling, stereochemical, mass spectrometry, and electron paramagnetic resonance spectroscopy) that will provide insight into the novel reaction pathways of these photoinduced, copper-catalyzed C–N bond-forming reactions. These mechanistic investigations will play an important role in facilitating our reaction-development program, as well as broadening our understanding of fundamental chemical reactivity.