Pd-Catalyzed decarboxylative alkynylation of alkynyl carboxylic acids with arylsulfonyl hydrazides via a desulfinative process

In the presence of a Pd(II)/P-ligand catalytic system, decarboxylative alkynylation of alkynyl carboxylic acids and arylsulfonyl hydrazides by desulfinative coupling could provide aryl alkynes in satisfactory yields by either judiciously selecting palladium catalysts or modulating phosphine ligands under mild conditions. The reported coupling reactions are very practical as they do not require the protection of inert gas or oxygen and are tolerant to many functional groups.