palladium(ii) phosphineylide complexes as highly efficient homogeneous pre-catalysts for the ullmann homocoupling reaction of aryl halides

A highly efficient ullmann homocoupling reaction of aryl halides using palladium(ii) phosphine-ylide complexes as homogenous precatalysts under aerobic conditions has been developed without the need for any chemical co-reducing agents. the procedure is relatively mild and appears to have broad applicability, being useful for the homocoupling of both electron-deficient and electron-rich aryl halides and also homocoupling of phenylboronic acid and phenylacetylene.