Pentafluoropropenyl Complexes of Mercury, Germanium, Tin, and Lead Derived from (Z)-CFHCFCF3 and Their Use as Transfer Reagents

A series of new (E)-pentafluoropropenyl complexes of Hg, Ge, Sn, and Pb are reported derived from CFHCFCF3 ((Z)-HFC-1225ye). Unequivocal assignment of the geometry of the products was achieved via a multinuclear (1H, 13C, 19F, 119Sn, and 199Hg) NMR study. These conclusions are confirmed in the single-crystal X-ray structures of Ph3Ge­(CFCFCF3) and Ph3Sn­(CFCFCF3). In the solid-state structures of both molecules, short contacts are observed between one of the fluorine atoms of the CF3 group and the metal center. The Bu3Sn­(CFCFCF3) compound acts as an effective source of the pentafluoropropenyl group in a series of palladium-catalyzed Stille–Liebeskind reactions to generate new aryl–pentafluoropropenyl systems.