Efficient and practical approach to esters from acids/ 2-oxoacids/ 2-oxoaldehydes &/ 2-oxoesters

An efficient, mild, cost effective and practical method is presented for generation of esters (RCO2R′) from acids (RCO2H)/ 2-oxoacids (RCOCO2H)/ 2-oxoaldehydes (RCOCHO)/ 2-oxoesters (RCOCO2R″) and alcohols by using oxone as catalyst. In addition to deciphering the scope of our process, we propose a mechanism for esterification through a common intermediate IV. Reaction with 2-oxoacids and 2-oxoaldehydes proceed with initial CO-C cleavage followed by oxone mediated esterification with alcohols. In addition, reaction with 2-oxoesters proceeds through CO-CO bond cleavage and trans-esterification.