Joaquina Ferrer

Synthesis, characterization and molecular structure of the hydroperoxo complex [(η5C5Me5)Ir(µ-pz)3Rh(OOH)(dppe)][BF4]; Hpz = pyrazole, dppe β 1,2-bis(diphenylphosphino)ethane

The synthesis and structural characterization of the title hydroperoxide complex is described.

Heterobinuclear IrRh, RuRh and Rulr complexes with pyrazolate bridging ligands: reactivity towards chelating diphosphines; crystal structure of [(C5Me5)Ir(µ-pz)2(µ-CO)-Ir(CO)(dppen)]BPh4·0.5MeOH [pz = pyrazolate, dppen =cis-1,2-bis(diphenylphosphino)ethylene]

Complexes of general formula [LClM(µ-pz)2M′(cod)]1–5[L = C5Me5, M = Rh or Ir; L =p-cymene, Me = Ru; M′= Rh or Ir; pz = pyrazolate; cod = cycloocta-T,5-diene (not all possible combinations)] and [(MeC6H4Pri-p)Ru(µ-pz)(µ-Cl)2Rh(cod)]7 were prepared starting from mononuclear acetylacetonate and pyrazole or pyrazolate-containing moieties. Complexes 1–5 react with CO yielding derivatives [LClM(µ-pz)2M′(CO)2]8–12. Complexes [(C5Me5)ClRh(µ-pz)2Rh(CO)2]13 and [(MeC6H4Pri-p)CIRu(µ-pz)2Ir(CO)2]12 react with NaX to give [(C5Me5)XRh(µ-pz)2Rh(CO)2](X = I, 14; or N3, 15) and [(MeC6H4Pri-p)[graphic omitted]rX(CO)2](X = Br, 16; or I, 17. The dicarbonyl compound 10 and [(MeC6H4Pri-p)CIRu(µ-pz)2M′(CO)2](M′= Rh, 11; or Ir, 12) react with diphosphines (L–L) or 1,2-bis(diphenylarsino)ethane (dpae) and NaBPh4 or AgBF4 affording cationic complexes [LM(µ-pz)2(µ-CO)M′(L–L)]A 23–31[L–L = bis(diphenylphosphino)methane, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, cis-1,2-bis-(diphenylphosphino)ethylene (dppen) or dpae; A = BPh4 or BF4(not all possible combinations)]. In this reaction intermediates [LM(µ-pz)2(µ-CO)M′(CO)(L–L)]A have been isolated in some cases. The crystal structure of one of these [(C5Me5)Ir(µ-pz)2(µ-CO)Ir(CO)(dppen)] BPh4·0.5MeOH 19 has been determined by X-ray diffraction methods. Crystals are monoclinic, space group P21/c, a= 15.996(2), b= 22.199(4), c= 18.874(3)A, β= 115.04(1)° and Z= 4. The complex cation consists of two iridium atoms bridged by two pyrazolates and one ketonic carbonyl group. An η5-C5Me5 ligand, a chelate dppen and a terminal CO group complete the co-ordination spheres of the iridium atoms, which are separated by 3.440(5)A.

Synthesis, X-ray structure, and nuclear magnetic resonance (1H and 13C) studies of ruthenium(II) complexes containing pyrazolyl ligands

The synthesis and n.m.r. spectra (1H and 13C) are reported for 24 p-cymeneruthenium complexes belonging to one of the following families: [Ru(MeC6H4Pri-p)(acac)X](3)–(9), [Ru(MeC6H4Pri-p)(acac)L]BF4(10)–(17), [Ru(MeC6H4Pri-p)ClL2]BF4(19)–(22), and [Ru(MeC6H4Pri-p)L3][BF4]2(23), [Ru(MeC6H4Pri-p)XL2]BF4(24), and [Ru(MeC6H4Pri-p)X2L](25), where X = Br, I, N3, pz, mpz, dmpz, or idz, and L = pyridine, PPh3, CNBut, P(OMe)3, Hpz (pyrazole), Hmpz (3-methylpyrazole), Hdmpz (3,5-dimethylpyrazole), and Hidz (indazole) for complexes (3)–(17), and only azoles (pyrazoles and indazole) for the remaining ones. Crystals of [Ru(MeC6H4Pri-p)(pz)(Hpz)2]BF4 are monoclinic, space group P21/c, with a= 9.882 6(2), b= 13.966 3(3), c= 31.690 2(15)A, β= 94.650(3)°, and Z= 8. The structure was determined by X-ray diffraction and refined to R= 0.045 (R′= 0.036). There are two crystallographic units, each having an intramolecular hydrogen bond between a pyrazole and a pyrazolate ring, and another between the other pyrazole ligand and the BF4 anion. The n.m.r. data (δ and J) of the azole complexes were carefully determined and are thoroughly discussed.