Examining the Scope of Deriving β-Aryl Enones from Enol Silanes as Ketone Equivalents via Pd(II)-Mediated Sequential Dehydrosilylation and Arylation

Silyl enol ethers were examined as a masked source ofsaturatedketones to derive beta-aryl enones and their derivatives by dehydrosilylationto generate enones in situ and subsequent oxidativearylation with arylboronic acids as transmetallation coupling partnersusing relayed Pd-(II) catalysis in one pot under base-free conditions.Oxygen was found to be an efficient and green oxidant to enable bothdehydrosilylation of enol silanes and arylation. Additionally, arylationconditions can be custom-designed to take advantage of aryl halidesas an alternative source of arylating agents. The preparative scopewas investigated with 35 examples (up to 95% yield), and mechanisticstudies implied a cationic Pd-(II)-based catalytic system.

Automated summary

This study discovered that silyl enol ethers can be used as a masked source of saturated ketones to produce beta-aryl enones and their derivatives through dehydrosilylation and subsequent oxidative arylation using Pd-(II) catalysis. Oxygen was found to be an efficient and environmentally friendly oxidant for both dehydrosilylation and arylation. The arylation conditions can be customized to utilize aryl halides as an alternative source of arylation agents. 35 examples were tested with up to 95% yield, and mechanistic studies revealed a cationic Pd-(II)-based catalytic system.