Synthesis of ketones by C-H functionalization of aldehydes with boronic acids under transition-metal-free conditions

Abstract

A method for the synthesis of ketones from aldehydes and boronic acids via a transition-metal-free C−H functionalization reaction is reported. The method employs nitrosobenzene as a reagent to drive the simultaneous activation of the boronic acid as a boronate and the activation of the C−H bond of the aldehyde as an iminium species that triggers the key C−C bond-forming step via an intramolecular migration from boron to carbon. These findings constitute a practical, scalable, and operationally straightforward method for the synthesis of ketones.