A Sterically Tuned 2-Fluoropyridinium Salt for the Catalyst-Free, Visible-Light-Mediated Deoxygenation of Alcohols via an Electron Donor-Acceptor Complex.

We here report the use of a sterically tuned 2-fluoro-1-methylpyridinium salt for the catalyst-free, visible-light-mediated deoxygenative transformation of alcohols through alkoxypyridinium intermediates. The key to this process is the introduction of a bulky cyclohexyl group at the 3-position of the pyridinium ring, which enforces a favorable conformation for C-O bond cleavage and the formation of an electron donor-acceptor complex between the pyridinium ring and amines.