(Chloro-phenylthio-methylene)dimethylammonium chloride (CPMA): a new coupling reagent for the formation of ester and amide bond

CPMA is an efficient agent for the formation of esters and amides from carboxylic acids. It is compatible with substrates that are sensitive to basic conditions or oxophilic reagents. The reaction proceeds without racemization of chirally labile carboxylic acids. All these advantages make CPMA a valuable adjunct to the existing arsenal of coupling reagents.