Transition-metal complexes containing phosphorus ligands. Part XV. ortho-Metallation reactions involving some triphenyl phosphite derivatives of ruthenium and rhodium

Abstract

The complexes [Ru(CO)(Cl)H(PPh₃)₃], [Ru(CO)H₂(PPh₃)₃], [Ru(CO)₃(PPh₃)₂], and [RuH₂(PPh₃)₄] react with triphenyl phosphite in hydrocarbon solvents to yield triphenyl phosphite derivatives which subsequently undergo ortho-metallation. Products which have been isolated and/or characterised include the substituted species [Ru(CO)(Cl)H(PPh₃)₂{P(OPh)₃}] and [Ru(CO)(Cl)H(PPh₃){P(OPh)₃}₂], and the metallated derivatives [Ru(CO)(Cl){P(OPh)₃}₂(pc)], [Ru(CO)H(PPh₃){P(OPh)₃}(pc)], [Ru(CO)H{P(OPh)₃}₂(pc)], and [Ru{P-(OPh)₃}₂(pc)₂][pc = P(OPh)₂(OC₆H₄)]. Attempts to reverse the metallation process by addition of hydrogen chloride or hydrogen to [Ru{P(OPh)₃}₂(pc)₂] under mild conditions have been usuccessful; however, this complex undergoes demetallation in the presence of perfluorocarboxylic acids, R_FCO₂H, to yield the species trans-[Ru(O₂CR_F)₂{P(OPh)₃}₄]·R_FCO₂H (R_F= CF₃ or C₂F₅). The rhodium complex [RhH{P(OPh)₃}₄] in boiling n-heptance loses hydrogen to yield the metallated product [Rh{P(OPh)₃}₃(pc)].