Electrochemical Synthesis and Photophysical Investigation of One and Two Electron Reduced Organic Photoredox Precatalysts

Organic photoredox catalysis is a profitable, emerging methodology in synthetic chemistry, making countless challenging chemical transformations easily accessible. For organic photocatalysts, the active catalyst responsible for single electron transfer to substrates was initially proposed to be the excited state of the radical anion of the photocatalyst, formed in-situ. Recently, the Nocera group has shown that for naphthalene monoimide, the species responsible for its super-reducing nature is actually the singlet excited state of its two electron reduced and singly protonated counterpart. This indicated that for radical organic anions thought to facilitate PRC, it might actually be the two electron reduced species that is formed in situ that is responsible for the observed reactivity. In order to gain more insight on the mechanism of photoredox catalysis mediated by known super-reducing species, the singly and doubly reduced counterparts of these organic molecules need to be isolated, which is typically challenging because of the air and moisture sensitivity, and instability of these intermediates. The objectives of this project are to develop an electrochemical protocol to generate and isolate one-electron and two-electron reduced products of some known organic photocatalysts, following which their photophysics and photochemistry relevant to reductive organic transformations can be studied.

Faculty Supervisor:

David Herbert

Student:

Partner:

Harvard University

Discipline:

Physics

Sector:

Education

University:

University of Manitoba

Program: