Dai Oyama

One-pot synthesis of cis-bis(2,2′-bipyridine)carbonylruthenium(II) complexes from a carbonato precursor: X-ray crystal structures and electron transfer processes of the series complexes

The reaction of Brønsted acids with cis-[Ru(bpy)2(CO3)] (bpy = 2,2′-bipyridine) under CO results in cleavage of the carbonato ligand and formation of cationic cis-[Ru(bpy)2(CO)L] n + complexes [L = ONO2 (1 +), OH2 (2 2+), Cl (3 +), OCOH (4 +), and OCOCH3 (5 +)]. The structures of 1 + and 2 2+ were confirmed by single-crystal X-ray diffraction. Crystal data for 1(PF6): monoclinic, P21/c, a = 10.5242(3), b = 15.4727(3), c = 14.6571(3) Å, β = 92.3219(9)°, V = 2384.77(9) Å3, Z = 4, D calcd = 1.806 g cm−3, 5460 unique reflections (R int = 0.032), R 1 = 0.0540 [I > 2σ(I)], wR 2 = 0.1642 (all reflections); crystal data for 2(ClO4)2 · H2O: monoclinic, C2/c, a = 20.4247(7), b = 10.0777(3), c = 15.6039(5) Å, β = 127.7569(8)°, V = 2539.31(14) Å3, Z = 4, D calcd = 1.769 g cm−3, 2895 unique reflections (R int = 0.036), R 1 = 0.0343 [I > 2σ(I)], wR 2 = 0.0907 (all reflections). Except for 2(PF6)2 the complexes exhibit oxidation at 1.02–1.30 V versus Fc+/Fc in acetonitrile. Bipyridine-centered reductions are also observed; these redox potentials depend on the nature of L. This convenient synthesis will be useful for producing cis-[Ru(bpy)2(CO)L] n +-type complexes in high yield.

Aqua­[2-(2-pyrid­yl)-1,8-naphthyridine-κ2N1,N2](2,2′:6′,2′′-terpyridine-κ3N,N′,N′′)ruthenium(II) bis­(hexa­fluorido­phosphate) acetone sesquisolvate

The asymmetric unit of the title compound, [Ru(C13H9N3)(C15H11N3)(H2O)](PF6)2·1.5C3H6O, consists of two crystallographically independent RuII complexes. Each complex is approximately octahedral with the RuII atom bound by an N,N′-coordinated 2-(2-pyridyl)-1,8-naphthyridine (pynp) ligand, a meridional 2,2′:6′,2′′-terpyridine (tpy) ligand and one aqua ligand. The tpy ligand is coordinated in a planar tridentate fashion with the central N atom closest to the RuII atom. The aqua ligand is trans to the pyridine N atom of pynp. The long Ru—O distances [2.150 (5) and 2.138 (5) Å] are typical for aqua ligands in polypyridyl ruthenium complexes. In the crystal, both intramolecular O—H⋯N and intermolecular O—H⋯O hydrogen bonds are observed.

(2,2'-Bipyridine-κN,N')chlorido[4'-(2,5-dimethoxy-phen-yl)-2,2':6',2''-terpyridine-κN,N',N'']ruthenium(II) hexa-fluorido-phosphate acetonitrile monosolvate.

In the title compound, [RuCl(C10H8N2)(C23H19N3O2)]PF6·CH3CN, the ligand environment about the RuII atom is distorted octahedral, with the substituted terpyridyl ligand coordinated in a meridional fashion, the bipyridyl ligand coordinated in a cis fashion and the Cl atom trans to one of the bipyridyl N atoms. The Ru—N distances are in the range 2.036 (2)–2.084 (2) Å with the exception of the central Ru—N bond from the terpyridyl ligand, which is shorter [1.9503 (19) Å], as expected. The pendant dimethoxyphenyl substituent is not coplanar with the terpyridyl unit; the dihedral angle between the central pyridyl ring and the benzene ring is 46.72 (11)°. The anion is disordered equally over two positions around an F—P—F bond axis.

cis,trans-Dicarbonyl­dichlorido[2-(2-pyrid­yl)-1,8-naphthyridine-κN1,N2]ruthenium(II)

The asymmetric unit of the title compound, [RuCl2(C13H9N3)(CO)2], consists of four crystallographically independent RuII complexes. Each RuII atom is in a distorted octahedral environment coordinated by two carbonyl ligands, two Cl atoms and a chelating 2-(2-pyridyl)-1,8-naphthyridine (pynp) ligand. The carbonyl ligands are cis to each other, while the Cl atoms are trans. Relatively short interatomic distances (2.60–2.67 Å) between the uncoordinated N atom of pynp and the C atom of the carbonyl imply a donor–acceptor interaction between the pynp and carbonyl ligands.

(OC-6-35-A)-Aquadicarbonylchlorido[2-(2-pyridyl)-1,8-naphthyridine-κ;2N1,N2]ruthenium(II) hexafluoridophosphate 2,2′-Bipyridine

A dicarbonylruthenium(II) complex containing bidentate 2-(2-pyridyl)-1,8-naphthyridine, as well as monodentate aqua and chlorido ligands, were isolated and characterized using spectroscopic techniques and single crystal X-ray diffraction. These data indicate that geometrical isomerization occurs during the substitution reaction involving a superacid. Density functional theory (DFT) calculations were performed on the plausible geometrical isomers. The DFT-optimized structures and calculated infrared spectra suggest that the experimentally obtained structure is stable.

2-(Pyridin-2-yl)pyridinium tri­fluoro­methane­sulfonate

Although in the title salt, C10H9N2+·CF3SO3−, the C—C and C—N bond lengths within the aromatic rings are normal, there is a considerable difference in the C—N—C angles at the protonated and unprotonated N atoms, viz. 123.42 (10) and 117.10 (11)°, respectively. Bifurcated N—H⋯X (X = N or O) hydrogen bonds form within the cation and between cation and anion. As a result, the cation exists in a cis conformation in the solid state. An obvious π–π contact is also present between the non-protonated pyridyl rings of neighbouring cations.

cis-Bis(2,2′-bipyridine-κ2N,N′)carbonyl­chloridoruthenium(II) hexa­fluorido­phosphate

In the title compound, [RuCl(C10H8N2)2(CO)]PF6, the RuII atom is coordinated in a distorted octahedral geometry by four N atoms of the bipyridine ligands, a carbonyl C atom and a chloride ion. The carbonyl and chloride ligands in the cation adopt a mutually cis arrangement and these are disordered over two sets of sites with site occupancies of 0.721 (6) and 0.279 (6). The Ru—N bond length [2.117 (2) Å] trans to the carbonyl ligand is slightly longer than the average of the other Ru—N bond lengths (2.08 Å), which can be explained by the expected trans influence of the carbonyl group. In the crystal, weak C—H⋯F interactions are observed between the complex cation and the PF6 − anion, leading to the formation of a three-dimensional supramolecular structure. The crystal studied was an inversion twin with twin fractions of 0.78 (4) and 0.22 (4).

Synthesis and Crystal Structure of Alkynylplatinum(IV) Complex Containing the Terpyridine Ligand

Reaction of square planar [ (C≡CPh)(tpy)]+ (tpy = 2,2′:6′,2′′-terpyridine) with bromine at low temperature provides a general route for the synthesis of octahedral alkynyl(terpyridine)platinum(IV) complex. In this first example of alkynyl(terpyridine)platinum(IV) complex, the alkynyl group is situated in trans position relative to the central nitrogen atom of the terpyridine ligand, and the two bromido ligands are situated in trans positions; an X-ray structural analysis has been completed for trans(Br)-[ Br2(C≡CPh)(tpy)]+.