New Members of the 1,3-Di(2-pyridyl)benzene Pro-Ligand Family Bearing Tri- or Tetra-Phenylethylene and Related Platinum(II) Complexes

1,3-di(2-pyridyl)benzene (dpybH) is a fascinating pro-ligand which is structurally similar to terpyridine but the central N atom is replaced by a CH moiety; when CH deprotonation occurs upon binding to a metal atom, then a cyclometallated compound is formed in which the N^C^N-bound ligand is isoelectronic with terpyridine, but it is an anionic ligand rather than a neutral ligand. In this study we prepared and thoroughly characterized two new pro-ligands, namely 1,3-bis(4-triphenylethylene-pyridin-2-yl)-4,6-difluoro-benzene and 1,3-bis(4-tetraphenylethylene-pyridin-2-yl)-4,6-difluoro-benzene, which open the doors for new N^C^N metal complexes. The related platinum(II) complexes, characterized by a weak emission in solution, were also synthesized.