A mild and efficient method for the synthesis of organic peroxyesters from acid chlorides and tertiary alkyl hydroperoxides in the presence of aqueous solution of inorganic base is described. The process was conducted in a tri-liquid system using quaternary onium salts and polyethylene glycols as phase-transfer catalysts. A model reaction of cumyl hydroperoxide (CHP) with butyryl chloride was investigated under a wide range of conditions. Selected peroxyesters were obtained in moderate to high yields (62-93%). (C) 2012 Elsevier B.V. All rights reserved.