Pd-Catalyzed room temperature hydrodeoxygenation of aryl sulfonates by tuning the stereoelectronic nature of ligands

A method for mild and efficient hydrodeoxygenation of aryl sulfonates is presented. Though a rational and careful adjustment of the stereoelectronic nature of bidentate phosphine ligands, the reaction could proceed very rapidly and efficiently at room temperature with 1 mol% Pd(OAc)2 as precatalyst and 2 mol% bis[(di-tert-butylphsophanyl)methyl]-substituted diphosphines as ligands, giving the products in high to excellent yields (71‒98%). The method showed a broad substrate scope including various fused and unfused aryl triflates, and delocalized aryl tosylates and mesylats. Moreover, the reaction could be reliably carried out at gram scale with only 0.1 mol% Pd(OAc)2 and 0.2 mol% ligand loading and tolerates a rich variety of reducible and Pd-sensitive functionalities. These advantages make the method more general and practical for the hydrodeoxygenation of aryl sulfonates.