Atom efficient preparation of zinc selenates for the synthesis of selenoesters under “On Water” conditions

The use of PhSZnBr as sulfenylating agent in a solvent-free protocol to prepare in excellent yields thiol esters from acyl chlorides is here reported. Products were efficiently obtained by grinding the neat reagents for 5 min in a mortar. DFT calculations showed that the coordination of solvent molecules to the metal center of PhSZnBr results in the destabilization of the frontier MOs, thus reducing the reactivity towards the acyl chloride if compared to solvent-free conditions. A possible mechanism based on the coordination of the carbonyl group of the acyl chloride to the metal center of PhSZnBr is proposed.