Selective Monoacylation of Diols and Asymmetric Desymmetrization of Dialkyl meso-Tartrates Using 2-Pyridyl Esters as Acylating Agents and Metal Carboxylates as Catalysts.

With 2-pyridyl benzoates as acylating agents and Zn(OAc)2 as a catalyst, 1,2-diols, 1,3-diols, and catechol were selectively monoacylated. Furthermore, the highly enantioselective desymmetrization of meso-tartrates was achieved for the first time, utilizing 2-pyridyl esters and NiBr2/AgOPiv/Ph-BOX in CH3CN or CuCl2/AgOPiv/Ph-BOX in EtOAc catalyst systems (up to 96% ee). The latter catalyst system was also effective for the kinetic resolution of dibenzyl dl-tartrate.