Dimethyl Sulfoxide Ligands Research Articles

Crystal structure of cis,fac-{N,N-bis-[(pyridin-2-yl)meth-yl]methyl-amine-κ(3) N,N',N''}di-chlorido-(dimethyl sulfoxide-κS)ruthenium(II).

The reaction of di­chlorido­tetra­kis­(dimethyl sulfoxide)­ruthen­ium(II) with N,N-bis[(pyridin-2-yl)meth­yl]methyl­amine aff­ords the title complex, [RuCl2(C13H15N3)(C2H6OS)]. The asymmetric unit contains a well-ordered complex mol­ecule. The N,N-bis­[(pyridin-2-yl)meth­yl]methyl­amine (bpma) ligand binds the cation through its two pyridyl N atoms and one aliphatic N atom in a facial manner. The coordination sphere of the low-spin d 6 RuII is distorted octahedral. The dimethyl sulfoxide (dmso) ligand coordinates to the cation through its S atom and is cis to the aliphatic N atom. The two chloride ligands occupy the remaining sites. The bpma ligand is folded with the dihedral angle between the mean planes passing through its two pyridine rings being 64.55 (8)°. The two N—Ru—N bite angles of the ligand at 81.70 (7) and 82.34 (8)° illustrate the distorted octa­hedral coordination geometry of the RuII cation. Two neighboring molecules are weakly associated through mutual intermolecular hydrogen bonding involving the O atom and one of the methyl groups of the dmso ligand. One of the chloride ligands is also weakly hydrogen bonded to a pyridyl H atom of another molecule.

Synthesis and structure of iridium complexes [Ph3PR][trans-IrCl4(DMSO)2

The reaction of sodium chloroiridate with acetonyl-, cyanomethyl-, and 2-butenyltriphenylphosphonium chloride in dimethyl sulfoxide was used to synthesize ionic iridium complexes [Ph3PR][trans-IrCl4(DMSO)2] (R = CH2C(O)Me, CH2CN, CH2CH=CHMe). The phosphorus atoms in the [Ph3RP]+ cations have a slightly distorted tetrahedral coordination. The dimethyl sulfoxide ligand in the octahedral anions [trans-IrCl4(DMSO)2] is coordinated to metal via sulfur atoms.

Crystal structure of di-μ-iodido-bis-[(dimethyl sulfoxide-κO)(tri-phenyl-phosphane-κP)copper(I)

The centrosymmetric dinuclear title compound, [Cu2I2(C2H6OS)2(C18H15P)2], represents the first example of a CuI complex ligated by an O-bound dimethyl sulfoxide ligand. In the crystal, the two tetrahedrally coordinated Cu(I) atoms are bridged by two μ2-iodido ligands in an almost symmetrical rhomboid geometry. The loose Cu⋯Cu contact of 2.9874 (8) Å is longer than the sum of the van der Waals radii of two Cu atoms (2.8 Å), excluding a significant cupriophilic inter-action in the actual dimer. C-H⋯O and C-H⋯I hydrogen bonding interactions as well as C-H⋯π(aryl) interactions stabilize the three-dimensional supramolecular network.

Synthesis and structure of the rhodium complex [Ph3MeP][RhBr4(DMSO)2-trans

The ionic complex, methyltriphenylphosphonium(I) trans-bis(dimethylsulfoxido)tetrabromorhodiate, was prepared by the reaction of sodium hexabromorhodiate with methyltriphenylphosphonium bromide in dimethyl sulfoxide and studied by X-ray diffraction. The phosphorus atom in the [Ph3MeP]+ cation has an almost undistorted tetragonal coordination (the CPC angles are 108.3(2)°–110.5(2)°, the P-C bonds are 1.779(6)–1.798(4) A). In the octahedral complex anion [RhBr4(DMSO)2-trans]−, the dimethyl sulfoxide ligands are coordinated by the sulfur atoms (Rh-S, 2.344(1), 2.336(1); Rh-Br, 2.4839(7)–2.4934(7) A; SRhS, 179.56(7)°; trans-BrRhBr, 179.30(3)°, 179.56(7)°) (CIF file CCDC no. 978748).

Crystal structure of chlorido-penta-kis(dimethyl sulfoxide-κO)chromium(III) dichloride.

In the complex cation of the title salt, [CrCl(C2H6OS)5]Cl2, the CrIII ion is coordinated by one chloride ligand and five O atoms from dimethyl sulfoxide (DMSO) ligands, leading to a slightly distorted octa­hedral coordination environment [O—Cr—O angles range from 86.69 (16) to 92.87 (16)°]. In the crystal, complex cations are arranged in hexa­gonally packed rows parallel to [010], with the chloride counter-anions situated in between. The inter­actions between cations and anions are mainly ionic in nature.

Structure and catalytic activity of the ruthenium(I) sawhorse-type complex [Ru2{μ,η2-CF3(CF2)5COO}2(DMSO)2(CO)4

The title compound, cis-di-μ-perfluoroheptanoato-κ(4)O:O'-bis[dicarbonyl(dimethyl sulfoxide-κS)ruthenium(I)](Ru-Ru), [Ru2(C7F13O2)2(C2H6OS)2(CO)4], is a sawhorse-type dinuclear ruthenium complex with two bridging perfluoroheptanoate ligands, and with two dimethyl sulfoxide (DMSO) ligands in the axial positions coordinating via the S atoms. It is a new example of a compound with an aliphatic fluorinated carboxylate ligand. The Ru-Ru bond distance of 2.6908 (3) Å indicates a direct Ru-Ru interaction. The compound is an active catalyst in transvinylation of propionic acid with vinyl acetate.

Formation and stability of calcium complexes of dimethyl sulfoxide in water

Dimethyl sulfoxide (DMSO) is widely utilized compound in biomedical and technological applications. Predominantly, it is used for biomembranes opening during a drug delivery procedure. The mechanism of DMSO membrane treatment is influenced by DMSO interactions with Ca2+ as well as with water presence. In this study we investigate Ca2+ interactions with DMSO in an aqueous environment using electrospray ionization mass spectrometry supported by density functional calculations. The number of DMSO ligands in [Ca(DMSO)x]2+ depends on the conditions during the electrospray and ion-transfer process. At capillary temperatures lower than 120°C the complexes with a high number of DMSO are preferentially transferred to the gas phase (e.g. [Ca(DMSO)6]2+). With increasing temperature the number of DMSO ligands decreases while they are replaced with water molecules. Both the experiment and the calculations show that the bonding energy of DMSO to Ca2+ is strongly influenced by the presence of water. The calculations also demonstrate that the bonding of DMSO to Ca2+ is rather strong; the Ca2+-DMSO bonding energy was calculated to be two times higher than the Ca-H2O bonding energy.

Silver–Organic Frameworks Containing Ethynediide or Ethynide with Ancillary Oligo-α-sulfanylpyrazinyl and Dimethylsulfoxide Ligands

Five new silver(I)–organic frameworks containing ethynediide or alkyl and aryl ethynide, together with newly designed oligo-α-sulfanylpyrazinyl ligands, namely, [(Ag2C2)2(AgCF3COO)11(L1)(μ2-DMSO)3(DMSO)5]·1/4H2O (L1 = 2,6-bis(pyridin-2-ylthio)pyrazine, 1), [(Ag2C2)2(AgCF3COO)11(L2)(μ2-DMSO)5(DMSO)3]·1/4H2O (L2 = 2-(pyrazin-2-ylthio)-6-(pyridin-2-ylthio)pyrazine, 2), [(AgC≡CtBu)2(AgCF3COO)5(L3)(DMSO)3(H2O)] (L3 = 2,6-bis(pyrazin-2-ylthio)pyrazine, 3), [(AgC≡CPh)4(AgCF3COO)2(L3)(DMSO)2]·DMSO·1/2H2O (4), and [(AgC≡CC6H4Cl-3)4(AgCF3COO)2(L3)(DMSO)]·H2O (5), have been synthesized and characterized by X-ray crystallography. Isomorphous complexes 1 and 2 feature an infinite coordination chain composed of (C2)2Ag15 clusters alternatively linked by L1 or L2 ligands; weak intermolecular C–H···F hydrogen bonding between adjacent infinite chains results in a three-dimensional supramolecular network. Complex 3 exhibits a coordination layer structure composed of (tBuC2)2Ag7 aggregates. Compounds 4 and 5 are nearly isos...

New Uses for Old Drugs: Attempts to Convert Quinolone Antibacterials into Potential Anticancer Agents Containing Ruthenium

Continuing the study of the physicochemical and biological properties of ruthenium-quinolone adducts, four novel complexes with the general formula [Ru([9]aneS3)(dmso-κS)(quinolonato-κ(2)O,O)](PF6), containing the quinolones levofloxacin (1), nalidixic acid (2), oxolinic acid (3), and cinoxacin (4), were prepared and characterized in solid state as well as in solution. Contrary to their organoruthenium analogues, these complexes are generally relatively stable in aqueous solution as substitution of the dimethylsulfoxide (dmso) ligand is slow and not quantitative, and a minor release of the quinolonato ligand is observed only in the case of 4. The complexes bind to serum proteins displaying relatively high binding constants. DNA binding was studied using UV-vis spectroscopy, cyclic voltammetry, and performing viscosity measurements of CT DNA solutions in the presence of complexes 1-4. These experiments show that the ruthenium complexes interact with DNA via intercalation. Possible electrostatic interactions occur in the case of compound 4, which also shows the most pronounced rate of hydrolysis. Compounds 2 and 4 also exhibit a weak inhibition of cathepsins B and S, which are involved in the progression of a number of diseases, including cancer. Furthermore, complex 2 displayed moderate cytotoxicity when tested on the HeLa cell line.

(2,2′-Bipyridine-κ2N,N′)tetrakis(dimethyl sulfoxide-κO)copper(II) bis(perchlorate)

The title compound, [Cu(C2H6OS)4(C10H8N2)](ClO4)2, contains a CuII ion with a distorted octa­hedral coordination environment, bonded by four O atoms of the monodentate dimethyl sulfoxide ligands and two N atoms of the bidentate chelating 2,2′-bi­pyridine ligand. The equatorial Cu—N and Cu—O bond lengths are in the range 1.979 (2)-1.998 (3) Å. The axial Cu—O bond distances are 2.365 (2) and 2.394 (2) Å. In the crystal, the complex cations and perchlorate anions are connected by numerous C—H⋯O hydrogen bonds, which leads to additional stabilization of the structure. The perchlorate anion is disordered over two sets of sites with a 0.716 (3):0.284 (3) occupancy ratio.

Cis-Dichloridotetrakis(dimethyl sulfoxide-κO)chromium(III) chloride dimethyl sulfoxide monosolvate

The structure of the title compound, [CrCl2(C2H6OS)4]Cl·C2H6OS, consists of a CrIII ion coordinated by four O atoms of dimethyl sulfoxide (DMSO) ligands and two chloride ions in cis positions, forming a distorted CrCl2O4 octa­hedron. An isolated Cl− counter-anion and a positionally disordered DMSO mol­ecule [occupancy ratio 0.654 (4):0.346 (4)] are also present. In the structure, the complex cations inter­act with the Cl− counter-anions and the DMSO solvent mol­ecules via weak C—H⋯Cl and C—H⋯O inter­actions, forming a three-dimensional network.

Aerobic Dehydrogenation of Cyclohexanone to Cyclohexenone Catalyzed by Pd(DMSO)2(TFA)2: Evidence for Ligand-Controlled Chemoselectivity

The dehydrogenation of cyclohexanones affords cyclohexenones or phenols via removal of 1 or 2 equiv of H2, respectively. We recently reported several Pd(II) catalyst systems that effect aerobic dehydrogenation of cyclohexanones with different product selectivities. Pd(DMSO)2(TFA)2 is unique in its high chemoselectivity for the conversion of cyclohexanones to cyclohexenones, without promoting subsequent dehydrogenation of cyclohexenones to phenols. Kinetic and mechanistic studies of these reactions reveal the key role of the dimethylsulfoxide (DMSO) ligand in controlling this chemoselectivity. DMSO has minimal kinetic influence on the rate of Pd(TFA)2-catalyzed dehydrogenation of cyclohexanone to cyclohexenone, while it strongly inhibits the second dehydrogenation step, conversion of cyclohexenone to phenol. These contrasting kinetic effects of DMSO provide the basis for chemoselective formation of cyclohexenones.

Synthesis and structure of palladium complexes [Ph3PhCH2P]+[PdCl3(DMSO)]− · DMSO, [Ph4P]+[PdCl3(DMSO)]−, and [Ph4Sb(DMSO)]+[PdCl3(DMSO)

[Ph3PhCH2P]+[PdCl3(DMSO)]− · DMSO (I), [Ph4P]+[PdCl3(DMSO)]− (II), and [Ph4Sb(DMSO)]+[PdCl3(DMSO)]− (III) complexes have been synthesized via the reaction of palladium chloride with equimolar amounts of triphenylbenzylphosphonium chloride, tetraphenylphosphonium chloride, and tetraphenylstibonium chloride, respectively. According to X-ray diffraction data, the cations of complexes I (CPC = 104.90(8)°–111.61(9)°) and II (CPC = 105.12(10)°–111.46(10)°) have slightly distorted tetrahedral structures with P-C bond lengths of 1.786(2)–1.809(2) and 1.791(2)–1.799(2) A, respectively. The antimony atom in the [Ph4Sb(DMSO)]+ cation has a trigonal bipyramidal surrounding with the dimethyl sulfoxide (DMSO) oxygen atom in an axial position (Sb...O 2.567(2) A). The palladium atoms in the square mononuclear anions of complexes I, II, and III are tetracoordinate, and Pd-Cl distances are 2.3101(5)–2.3104(5) A, 2.2950(7)–2.2038(7) A, and 2.2986(9)–2.3073(9) A, respectively. The DMSO ligands are coordinated to the palladium atom through the sulfur atom (Pd-S, 2.2318(5) (I), 2.2383(6) (II), and 2.2410(9) A (III)).

Dibromido(2,9-dimethyl-1,10-phenanthroline-κ2N,N′)(dimethyl sulfoxide-κO)cadmium

In the mol­ecule of the title compound, [CdBr2(C14H12N2)(C2H6OS)], the CdII atom is five-coordinated in a distorted trigonal–bipyramidal configuration by two N atoms from a 2,9-dimethyl-1,10-phenanthroline ligand, one O atom from a dimethyl sulfoxide ligand and two Br atoms. In the crystal, π–π contacts between the pyridine and benzene rings [centroid–centroid distances = 3.710 (5), 3.711 (6) and 3.627 (5) Å] stabilize the structure.

Trichlorido(dimethyl sulfoxide-κO)(di-2-pyridylamine-κ2N,N′)indium(III)

In the title compound, [InCl3(C10H9N3)(C2H6OS)], the InIII atom is six-coordinated in a distorted octa­hedral geometry by two N atoms from a chelating di-2-pyridyl­amine ligand, one O atom from a dimethyl sulfoxide ligand and three Cl atoms. Inter­molecular C—H⋯Cl hydrogen bonds and π–π contacts between the pyridine rings [centroid–centroid distance = 3.510 (3) Å] are present in the crystal.

Dibromido(dimethyl sulfoxide-κO)(6-methyl-2,2′-bipyridine-κ2N,N′)cadmium

In the title compound, [CdBr2(C11H10N2)(C2H6OS)], the CdII atom is five-coordinated in a distorted trigonal–bipyramidal geometry by two N atoms from a 6-methyl-2,2′-bipyridine ligand, one O atom from a dimethyl sulfoxide ligand and two Br atoms. An intra­molecular C—H⋯O hydrogen bond occurs. The crystal structure is stabilized by C—H⋯Br hydrogen bonds and π–π contacts between the pyridine rings [centroid–centroid distances = 3.582 (5) and 3.582 (5) Å].

Dibromido(4,4′-dimethyl-2,2′-bipyridine-κ2N,N′)(dimethyl sulfoxide-κO)cadmium

In the title compound, [CdBr2(C12H12N2)(C2H6OS)], the CdII atom is five-coordinated in a distorted trigonal–bipyramidal geometry by two N atoms from one 4,4′-dimethyl-2,2′-bipyridine (DMBP) ligand, one O atom from a dimethyl sulfoxide (DMSO) ligand and two Br atoms. A weak intra­molecular C—H⋯O hydrogen bond occurs between the DMBP and DMSO ligands. π–π stacking between pyridine rings [centroid–centroid distances = 3.682 (3) and 3.598 (3) Å] is observed in the crystal.

Octakis(dimethyl sulfoxide-κO)cerium(III) μ6-oxido-dodeca-μ2-oxido-hexaoxidohexamolybdate(VI) dimethyl sulfoxide tetrasolvate

The title complex, [Ce(C2H6OS)8]2[Mo6O19]3·4C2H6OS, was obtained as a byproduct of the reaction of [(C4H9)4N]2[Mo6O19] with Ce(NO3)3·6H2O and phthalic acid in dimethyl­sulfoxide solution. The asymmetric unit consists of a complex [Ce(C2H6OS)8]3+ cation, one and a half of the Lindqvist-type [Mo6O19]2− polyanions and two dimethyl­sulfoxide solvent mol­ecules; the half polyanion lies on an inversion center. The Ce3+ ion is coordinated by eight dimethyl­sulfoxide ligands through the O atoms in the form of a distorted square antiprism. The Ce—O bond lengths range from 2.429 (6) to 2.550 (5) Å. The cohesion of the structure is ensured by S⋯O [3.115 (6), 3.242 (10) and 3.12 (3) Å], O⋯O [3.037 (10) Å] and C—H⋯O inter­actions between cations and anions. The S and C atoms of a dmso ligand are disordered over three sites in a 0.45:0.30:0.25 ratio. The dimethyl­sulfoxide solvent mol­ecules are highly disordered and could not be modelled successfully; their contribution was therefore removed from the refinement using the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148–155]. Potential solvent-accessible voids of 500.0 Å3 occur in the crystal structure.

Hexakis(dimethyl sulfoxide-κO)calcium μ6-oxido-dodecakis-μ2-oxido-hexaoxidohexatungstate(VI)

In the title compound, [Ca(C2H6OS)6][W6O19], the cation and anion both have a crystallographically imposed centre of symmetry. The CaII atom in the cation is coordinated by six O atoms from six dimethyl sulfoxide ligands in a distorted octa­hedral geometry. The [W6O19]2− isopolyanion possesses the well-known Lindqvist structure in which each WVI atom is coordinated by four μ2-O, one terminal O and one μ6-O atom.

Tetra-kis{2-[2-(2,6-dichloro-anilino)phen-yl]ethano-ato-κ(2)O:O'}bis-[(dimethyl sulfoxide-κO)copper(II)](Cu-Cu): a binuclear Cu(II) complex with the non-steroidal anti-inflammatory drug diclofenac.

The title compound, [Cu2(C14H10Cl2NO2)4(C2H6OS)2], comprises a CuII 2 core that is quadruply bridged by four carboxyl­ate ligands with the dimethyl sulfoxide ligands binding along the Cu⋯Cu axis. The four carboxyl­ate ligands bind in a bidentate syn–syn bridging mode. Mol­ecules reside on crystallographic inversion centres bis­ecting the mid-point of the Cu⋯Cu axis. There are no inter­molecular inter­actions of note.