N,N ',N ''-triphenylguanidinate(-1) complexes of ruthenium, osmium and iridium: synthesis and X-ray crystal structures

N,N',N"-Triphenylguanidine (TpgH) reacts with [Ru(H)(2)(CO)(PPh3)(3)] in re fluxing toluene and with [Os(H)(2)(CO)(PPh3)(3)] in refluxing o-xylene to y ield the guanidinate(- 1) complexes [RuH(Tpg)(CO)(PPh3)(2)] (1) and [Os(Tpg )(2)(CO)(PPh3)] (2), respectively. The reaction of TpgH with [RuCl2(PPh3)(3 )] in refluxing toluene affords a new route to the known complex [Ru(Tpg)(2 )(CO)(PPh3)] (3). Finally the reaction of mer-[Ir(H)(3)(PPh3)(3)] with TpgH in refluxing toluene yields the iridium(III) dihydride complex [Ir(H)(2)(T pg)(PPh3)(2)] (4). X-ray crystal structure determinations are reported for (1) and (4). (C) 2000 Elsevier Science S.A. All rights reserved.