A Regioselective, One-Pot, Transition-Metal-Free α-Alkylation of Quinone Monoacetals for Various Organic Transformations

Org Lett. 2024 Nov 5. doi: 10.1021/acs.orglett.4c03430. Online ahead of print.

Abstract

Regioselective reactions of biologically significant quinones are challenging. An unprecedented advancement in quinone monoacetal (QMA) chemistry is proposed for constructing regioselective and less explored α-alkylated QMAs through the Morita-Baylis-Hillman (MBH) reaction. Electrophilic QMAs were transformed to nucleophilic umpolung reagents for aldol-type condensation with several electrophiles. Mechanistic studies reveal that solvent (TFE:water (1:1)) and in situ-generated potassium acetate accelerate the reaction. The ensuing MBH adducts were scalable and underwent several post-synthetic transformations and late-stage functionalization.