Palladium Catalyzed α,β-Homodiarylation of Vinyl Esters in Aqueous Medium

Abstract A palladium catalyzed 1,2-diarylation of vinyl esters with sustainable arylbornic acids in water has been developed. This newly elaborated protocol features good functional group tolerance and provides a one-step access to 1,2-diaryletahol derivatives under mild reaction conditions. The presented reaction can be carried out in water smoothly without the addition of any ligands at ambient temperature what makes this procedure environmentally benign. The transformation occurs within a single catalytic cycle and is feasible due to the modification of transition metal catalytic activity through the influence of π-acceptor olefin (benzoquinone) as well as the polar protic reaction medium (water in particular). Moreover, the protocol allows to generate entire compounds libraries (highly profitable in medicinal chemistry) and utilizes sustainable arylboronic acid as coupling partners under mild conditions.