Palladium-catalysed Suzuki–Miyaura coupling of α,β-unsaturated superactive triazine esters†
Abstract
Palladium-catalysed Suzuki–Miyaura couplings of α,β-unsaturated acid derivatives are challenging due to the susceptibility of their CC bonds adjacent to carbonyl groups. In this work, we describe a highly selective C–O activation approach to this transformation using superactive triazine esters and organoborons as coupling partners. 42 α,β-unsaturated ketones with diverse functional groups have been prepared with this method. The mechanistic investigation unveiled that the dual function of triazine for activating the C–O bond and stabilizing non-covalent interactions between the catalyst and substrate is critical for the reaction's success. The method's efficiency, functional group compatibility and unique mechanism make it a valuable alternative to classic methods.