PN3(P)-Pincer Complexes: Cooperative Catalysis and Beyond

The tridentate pincer ligands, that enforce the meridional coordination around the metal center upon complexation, have become a powerful platform in catalyst design because of the enhanced stability and flexibility for synthetic modifications. The historical development, progress, and more importantly the distinct potential of the PN 3 (P)-pincer chemistry in several aspects, including reactivities of the PN 3 (P)-pincer complexes, with emphasis on the metal-ligand cooperation (MLC) via dearomatization/rearomatization, are discussed. Other aspects considered are the rationale for the kinetic and thermodynamic differences caused by the replacement of the CH 2 spacers with NH groups in the PN 3 (P)-pincer platform and the future potential of the PN 3 (P)-pincer chemistry.