REACTIONS OF COORDINATED TETRAFLUOROETHYLENE WITH HALOGENS - SYNTHESIS OF SIGMA-BONDED HALOTETRAFLUOROETHYL COMPLEXES OF RUTHENIUM(II) AND OSMIUM(II) AND THE STRUCTURE OF OSI(C2F4I)(CO)(2)(PPH(3))(2)

The reactions of eta(2)-C2F4 complexes of ruthenium and osmium with ha logens give rise to complexes containing a halotetrafluoroethyl ligand , e.g., M(eta(2)-C2F4)(CO)(2)(PPh(3))(2) (M = Ru or OS) With iodine or chlorine gives MX(C(2)F(4)X)(CO)(2)(PPh(3))(2)(M = Ru or Os; X = I or CI). Similarly, Os(eta(2)-C2F4)(CO)(CNR)(PPh(3))(2) reacts with iodin e to give OsI(C2F4I)(CO)(CNR)(PPh(3))(2), and Os(eta(2)-C2F4)Cl(NO)(PP h(3))(2) gives OsCl2(C2F4Cl)(NO)(PPh(3))(2) upon treatment with chlori ne. The ruthenium halotetrafluoroethyl compounds decompose readily to form RuX(2)(CO)(2)(PPh(3))(2), but the osmium halotetrafluoroethyl com plexes proved to be quite unreactive, even towards abstraction of alph a-fluoride. The crystal structure of OsI(C2F4I)(CO)(2)(PPh(3))(2) has been determined.