Carbonyl complexes of rhodium(I) and rhodium(III) with 2,2′-biquinoline

Novel carbonyl complexes of rhodium(I) and rhodium(III) containing the bidenate nitrogen donor ligand 2,2′-biquinoline (biq) have been prepared; they are of the types RhX(CO)2 biq and RhX(CO)biq (X = Cl, Br, I). Cationic carbonyl and substituted carbonyl complexes of the types [Rh(CO)2biq]ClO4 and [Rh(CO)biqL2]ClO4, where L is tertiary phosphine or arsine have also been isolated. In spite of considerable steric crowding around the nitrogen atoms, 2,2′-biquinoline behaves much like 2,2′-bipyridine in forming carbonyl complexes of rhodium. © 1979

Cationic carbonyl complexes of rhodium(I)

A number of cationic Rh(I) complexes of the type [Rh(CO)​2Q]​ClO4, [Rh(CO)​2L3]​ClO4, and [Rh(CO)​QL2]​ClO4, where Q = 2,​2'-​bipyridine or 1,​10-​phenanthroline and L is a tertiary phosphine or arsine, were isolated and their structures assigned. The configuration of the complex ion [Rh(CO)​2L3]​+ appears to depend critically on the size of the ligand L

2,​2'Bipyridyl and o-​phenanthroline carbonyl complexes of rhodium

CO was passed through an alc. soln. of Rh perchlorate contg. 2,​2'-​bipyridine (L) or o-​phenanthroline (L1) to give [Rh(CO)​2L]​ClO4 (I)​, m. 200-​5°, and [Rh(CO)​2L1]​ClO4 (II)​, m. 195-​200°, resp. With PPh3 and AsPh3 under similar conditions, [Rh(CO)​2(PPh3)​3]​ClO4 (III)​, m. 160-​2°, and [Rh(CO)​2(AsPh3)​3]​ClO4 (IV)​, m. 198-​9°, resp., were obtained. I and II were also obtained by passing CO through a hot alc. soln. of RhCl3.3H2O until the soln. turned yellow and then adding at ice temp., an excess of NaClO4 and L or L1, resp. I and II in EtOH were treated with PPh3 to give [Rh(CO)​L(Ph3P)​2]​ClO4, m. 150-​2°, and [Rh(CO)​L1(Ph3P)​2]​ClO4, m. 148-​53°, resp. These latter 2 compds. were also obtained by the addn. of L or L1 to an EtOH soln. contg. III. Similarly prepd. was [Rh(CO)​L(Ph3As)​2]​ClO4, m. 205-​8°. The complexes were characterized by elemental anal., ir spectra, and cond. measurements. I, II, III, and IV react with Ph3PO in excess releasing all CO present

Hydrido complexes of iridium with a tertiary arsine

α-​and β-​IrHX2(Ph2AsMe)​3 (X = Cl, Br, I) were prepd. and characterized. The α-​compds. were prepd. by treating the IrX3 in the arsine in alc. with Zn and the corresponding HX; while the β-​compds. were prepd. by refluxing IrX3 and the arsine in alc. in the presence of KOH. The compds. were characterized by m.p. and ir spectra

Cationic complexes of platinum and palladium with p-tolyl isocyanide

Cationic complexes of platinum and palladium of the type [MCl(p-CH3C6H4NC)L2]ClO4 (M = Pt, Pd; L = p-tolyl3P, o-tolyl3P, Cy3P, Ph2MeAs, Ph2EtAs, Ph2PrAs, Cy3As; Cy = cyclohexyl) have been isolated. These show a v(CN) band at ca. 2200 cm-1 compared with 2130 cm-1 for the free isocyanide ligand, suggesting weak π-character in the metal-carbon bond. The PMR spectra of the cationic complexes indicate trans configurations for the complexes. © 1977

Complexes of ruthenium(II) and ruthenium(III) with tertiary arsines

Ruthenium trichloride reacts with stoichiometric amounts of tertiary arsines in boiling ethanol to give paramagnetic complexes, RuCl3(Ph2RAs)3 (R = Me, Et, Pr, Bu), which react further with 2,2′-bipyridyl(bipy) and o-phenanthroline(phen) to yield brick red crystalline products, RuCl3 (N-N)(Ph2RAs) (N-N = bipy, phen). In the presence of excess arsine Ru(III) is reduced to Ru(II), and trichloro-bridged complexes of the formula [Ru2Cl3(Ph2RAs)6]Cl are formed. These on treatment with carbonylated solutions of rhodium chloride produce yellow crystals of [Ru2Cl3(Ph2RAs)6][RhCl2(CO)2] containing Ru(II) and Rh(I). Several dicarbonyl complexes cis-RuX2(CO)2(Ph2RAs)2 (X = Cl, Br; R = Pr, Bu) have also been isolated. © 1977

Reactions of rhodium and iridium salts with multidentate N-heterocycles

Complexes of rhodium and iridium of the types MX3L, MX(CO)2L and MX3(CO)L (X = halide) containing multidentate N-heterocycles (L), 2,6-bis(benzimidazolyl)pyridine (bBzlH2py) and 2,6-bis(N-methyl-benzimidazolyl)pyridine (bBzlMe2py) have been prepared and characterized by IR, electronic and 1H and 13C NMR spectral data. RhX(CO)2L, on treatment with alcoholic solvents or DMF undergoes reversible decarbonylation to produce RhXL·2H2O. Passage of NO or O2 through the carbonyl suspended in hot 2-methoxyethanol releases CO2. Copyright © 1997 Elsevier Science Ltd

Cyclometallation of bis-benzimidazole derivatives with rhodium(III) halides

Treatment of rhodium(III) halides with the N-heterocycles (LH), 1,3-bis(benzimidazolyl)benzene (bBzlH2bzH; Ia) and its N-methyl derivative (bBzlMe2bzH; Ib) in methanol gave halobridged binuclear cyclometallated products of the composition RhX2L2 (X=Cl, Br or I). The chloro complex undergoes halobridge cleavage reactions to yield several new mononuclear complexes of the types RhCl2(bBzlH2bz)(AsPh3), RhCl(bBzlH2bz)(OClO3)(Lâ²/N-N) (Lâ²=AsPh3; N-N=2,2â²-bipyridine or 1,10-phenanthroline) and the heterocycle bridged binuclear complexes of the composition RhCl2(bBzlH2bz)2(μ-N-N) (N-N=pyrazine or 4,4â²-bipyridine). Passage of CO through RhCl2(bBzlH2bz)2 in DMF yielded mononuclear carbonyl complex RhCl2(CO)(bBzlH2bz)·2H2O. Treatment of carbonylated solution of rhodium trichloride with Ia produced non-cyclometallated mononuclear complex of the type Rh(CO)2(bBzlH2bzH)Cl. The complexes are characterised by 1H, 13C NMR, IR, Far-IR, electronic and FAB-mass spectral studies. © Elsevier Science Ltd

Complexes of osmium with tertiary arsines and carbonmonoxide

Osmium halides (Cl and Br) react with monotertiary arsines Ph2RAs (R=Me, Et, Pr and Bu) in alcoholic medium to give paramagnetic octahedral complexes of the type OsX3L3 (X=Cl, Br; L=Ph2RAs) which further react with carbonmonoxide to give dihalo dicarbonyl complexes of osmium(II) of the type OsX2 (CO)2 L2. Similarly, osmium halides react with tertiary arsines in the presence of formaldehyde to give monocarbonyl complexes of osmium(II) of the type OsX2 (CO)L3. Structures have been assigned to all these compounds on the basis of IR and NMR studies. © 1980 Indian Academy of Sciences

arbonyl complexes of rhodium and iridium with tricyclohexyl arsine

Tricyclohexylarsine (L) complexes of Ir and Rh carbonyls were prepd. Thus, treating the carboxylation mixt. from Rh halides with L gave RhXL2(CO) (X = Br, Cl) which added X2 to give RhX3L2(CO)​. Treating the Ir analogs with HX gave IrHX2(CO)​L2, which by dehydrohalogenation gave mixed IrX(CO)​L2 and IrX(CO)​(O)​2L2