A Greener Approach toward Ynones via Visible-Light-Induced Oxidation of Propargyl Alcohols under Aqueous-Aerobic Conditions.

A simple and convenient approach involving visible-light-induced, TBHP-mediated oxidation of propargyl alcohols to ynone in aqueous media has been developed. This photoinduced protocol was conducted under an aerobic-aqueous medium using Eosin Y as a photosensitizer. A diverse range of ynone derivatives were prepared from propargyl alcohol in moderate to excellent yield. Furthermore, the successful gram-scale experiment of this method also indicates its flexibility and applicability for industrial applications. Steric mapping of the series 2a-2q, exemplified by 2j, revealed an optimized buried volume and three-dimensional bulk distribution that closely mimics the reference PKC inhibitor while surpassing the less efficient steric profiles of the MSY and VCAM1 analogues. In addition, an exit vector analysis was carried out to get a clearer insight into the substituent orientation and spatial vector divergence.