Regioselective and stereospecific palladium(0)-catalyzed reactions of 4-chloroacetoxyalk-2-enoic esters with carbon and nitrogen nucleophiles

Abstract

In the presence of a palladium(0) catalyst, treatment of 4-chloroacetoxyalk-2-enoic esters with carbon or nitrogen nucleophiles leads to the regioselective substitution at the 4-position. The reactions of optically active esters, prepared from an optically active phenylsulphinylacetic ester and aldehydes, take place with retention of configuration, and those of (E)- and (Z)-esters are not accompanied by the complete geometrical isomerization. The palladium(0)-catalyzed reactions of these esters are assumed to proceed through unsymmetrical π-allyl complexes.