β-Scission of Simple, Linear, Secondary Alcohols via Alkoxy Radical Generation

Abstract

β-scission, one of the productive pathways undergone by alkoxy radical species, allows for carbon-carbon bond dissociation and can be a powerful synthetic tool. While the instigation of β-scission using alcohol substrates has received attention in the literature, no group has yet demonstrated high-yielding β-scission on simple, linear, secondary alcohols. Motivated by potential applications in both sustainability and synthetic chemistry, optimizations of photocatalytically-driven β-scission reactions using such simple alcohol substrates are reported herein. A modest yield of 14% is demonstrated in the β-scission of 5-nonanol using an iridium photocatalyst; trace yields are also reported using an organic photocatalyst. Experimental and computational studies are performed on 6-undecanol’s corresponding alkoxy radical, which show disfavoring of the β-scission reaction pathway. The results, synthesized, suggest that the photocatalytic method applied herein is uniquely effective at instigating alkoxy radical generation for β-scission. Problems in the experimental system pertaining to product instability are analyzed, and suggestions for future work are put forth.