Tetraaquabis(D-camphor-10-sulfonato)calcium(II)

The structure of the title compound, [Ca(C(10)H(15)O(4)S)(2)(H(2)O)(4)], is the first example in which two D-camphor-10-sulfonate anions are coordinated to a metal ion, in this case with direct Ca-O bonding. The molecule has crystallographically imposed twofold symmetry with the Ca atom on the twofold axis. Hydrogen bonds are formed between the coordinated water molecules and the O atoms of the SO(3)(-) groups of adjacent molecules, leading to the formation of a two-dimensional layered network. The compound displays sharp wavelength-selective transparency in the UV-visible spectrum, offering the potential for application as an optical filter.

(S,S)-N,N'-Bis(1-carb-oxy-2-methyl-prop-yl)ethyl-enediammonium dihalide cyclo-penta-nol tetra-solvate (halide = bromide/chloride ≃ 1:12)

In the crystal structure of the title compound, C(12)H(26)N(2)O(4) (2+)·2(Br(0.085)Cl(0.915))(-)·4C(5)H(9)OH, the complete cation is generated by crystallographic twofold symmetry. Contamination of the chloride counter-anion with bromide occured during the preparation, due to the use of 1,2-dibromo-ethane. One of the solvent mol-ecules is disordered, with occupancies 0.53 (3):0.47 (3). The crystal packing is stabilized by an infinite two dimensional ⋯X⋯H-N-H⋯X⋯ hydrogen-bonding network (X: Br(-)/Cl(-) ≃ 1:12). In addition, O-H⋯X and O-H⋯O hydrogen bonds involving solvent mol-ecules are observed.

Platinum(II) tetramesityltetraphosphane-1,4-diides

[Na(2)(thf)(4)(P(4)Mes(4))] () (Mes = 2,4,6-Me(3)C(6)H(2)) reacts with one equivalent of [PtCl(2)(cod)] (cod = 1,5-cycloctadiene) or [PtCl(2)(dppe)] (dppe = bis(diphenylphosphino)ethane) to give the corresponding platinum(II) tetramesityltetraphosphane-1,4-diide complexes [Pt(P(4)Mes(4))(cod)] () and [Pt(P(4)Mes(4))(dppe)] (). The Pt-P bonds of these complexes proved to be extraordinarily stable and did not react with insertion reagents such as tert-butyl isocyanide or cyclohexyl isocyanide. Instead, ligand transfer occurred to give [Pt(P(4)Mes(4))(C[triple bond, length as m-dash]NBu(t))(2)] () and [Pt(P(4)Mes(4))(C[triple bond, length as m-dash]NCy)(2)] (). Further reactions of with CO, CS(2), white phosphorus, MeI and ethyl diazoacetate led either to formation of cyclo-P(4)Mes(4) and cyclo-P(3)Mes(3) or to unidentified products, in which no evidence of insertion of these reagents into the Pt-P bond was observed.

Bis[1,2-bis(dimethylphosphino)ethane-κ2P,P′]rhodium(I) dichlorido[(1,2,5,6-η)-1,5-cyclooctadiene]rhodium(I)

In the title complex, [Rh(C₆H₁₆P₂)₂][RhCl₂(C₈H₁₂)], the asymmetric unit contains two [Rh(dmpe)₂] [dmpe = 1,2-bis­(dimethyl­phosphino)ethane] half-cations, lying on inversion centers, and an [RhCl₂(cod)]⁻ (cod = 1,5-cyclo­octa­diene) anion, wherein Rh is coordinated by two chloride ligands and two olefinic π-bonds of the cyclo­octa­diene ligand. The Rh atoms in the cations and anion exhibit square-planar coordination and are separated without any unusual inter­actions.

Study of the cytotoxic activity of di and triphenyltin(IV) carboxylate complexes

The reaction of 3-methoxyphenylacetic acid (3-MPAH), 4-methoxyphenylacetic acid (4-MPAH), 2,5-dimethyl-3-furoic acid (DMFUH) or 1,4-benzodioxane-6-carboxylic acid (BZDOH) with triphenyltin(IV) chloride (1:1) or diphenyltin(IV) dichloride (2:1) in the presence of triethylamine yielded the compounds [SnPh3(3-MPA)] (1), [SnPh3(4-MPA)] (2), [SnPh3(DMFU)] (3), [SnPh3(BZDO)] (4), [SnPh2(3-MPA)2] (5), [SnPh2(4-MPA)2] (6), [SnPh2(DMFU)2] (7) and [SnPh2(BZDO)2] (8), respectively. The tetranuclear complex [{Me2(DMFU)SnOSn(DMFU)Me2}2] (9) was prepared by the reaction of dimethyltin(IV) oxide and 2,5-dimethyl-3-furoic acid (DMFUH). The molecular structures of 3, 4 and 9, were determined by X-ray diffraction studies. The cytotoxic activity of the carboxylic acids (3-MPAH, 4-MPAH, BZDOH and DMFUH) and di (5-8) and triphenyltin(IV) complexes (2-4) was tested against tumor cell lines human adenocarcinoma HeLa, human myelogenous leukemia K562, human malignant melanoma Fem-x and normal immunocompetent cells, peripheral blood mononuclear cells PBMC. Triphenyltin(IV) complexes show higher activities than the diphenyltin(IV) derivatives. The most active compound is [SnPh3(DMFU)] (3) with IC50 value of 0.15+/-0.01, 0.051+/-0.004, 0.074+/-0.004, 0.20+/-0.01, 0.15+/-0.02 on HeLa, K562, Fem-x, rested and stimulated PBMC, respectively, while the most selective are [SnPh2(3-MPA)2] (5), [SnPh(2)(DMFU)2] (7) and [SnPh((BZDO)2] (8). Compounds 3, 5, 7 and 8 present higher activities than cisplatin in all the tested cells and relative high selectivity especially on K562 cells.

Hexaaqua-magnesium(II) bis-(d-camphor-10-sulfonate)

The structure of the title complex, [Mg(H₂O)₆](C₁₀H₁₅O₄S)₂, consists of regular octa­hedral [Mg(H₂O)₆]²⁺ cations and d-camphor-10-sulfonate anions. A three-dimensional supra­molecular architecture is formed via hydrogen-bond inter­actions [O—H⋯O = 2.723 (2)–2.833 (2) Å] to give alternating layers of [Mg(H₂O)₆]²⁺ cations and d-camphor-10-sulfonate anions. The title compound is isomorphous with the zinc, copper, cadmium and nickel analogues.

Different transmetallation behaviour of [M(P4HR4)] salts toward rhodium(I) and copper(I) (M = Na, K; R = Ph, Mes; Mes = 2,4,6-Me3C6H2)

[K(2)(P(4)Mes(4))] (1) or [Na(2)(THF)(4)(P(4)Mes(4))] (2) (Mes = 2,4,6-Me(3)C(6)H(2)) reacts with one equivalent of HCl and subsequently with 0.5 equivalents of [{RhCl(cod)}(2)] (cod = 1,5-cyclooctadiene) to give a mixture of rhodium complexes, from which [Rh(P(4)HMes(4))(cod)] (3) and the secondary product [Rh(2)(micro-P(2)HMes(2))(mu-PHMes)(cod)(2)] (4) were isolated and characterised by X-ray diffraction studies. Alternatively, the reaction of [K(2)(P(4)Ph(4))] (5) or [Na(2)(THF)(5)(P(4)Ph(4))] (6) with one equivalent of HCl and subsequently with one equivalent of [CuCl(PCyp(3))(2)] (Cyp = cyclo-C(5)H(9)) gave the complex [Cu(4)(P(4)Ph(4))(2)(PH(2)Ph)(2)(PCyp(3))(2)] (7), presumably via disproportionation of the monoanion (P(4)HPh(4))(-).

Synthesis, structural characterization and cytotoxic activity of two new organoruthenium(II) complexes

Two new p-cymene ruthenium(II) complexes containing as additional ligands N-methylpiperazine ([(?6-p-cymene)RuCl2(CH3NH(CH2)4NH)]PF6, complex 1) or vitamin K3-thiosemicarbazone ([(?6-p-cymene)RuCl2(K3tsc)], complex 2) were synthesized starting from [(?6-p-cymene)2RuCl2]2 and the corresponding ligand. The complexes were characterized by elemental analysis, IR, electronic absorption and NMR spectroscopy. The X-ray crystal structure determination of complex 1 revealed ?piano-stool? geometry. The differences in the cytotoxic activity of the two complexes are discussed in terms of the ligand present.

The versatile reactivity of cyclo-(P5tBu4)- with complexes of the nickel triad

Na[cyclo-(P(5)tBu(4))] (1) reacts with [NiCl(2)(PEt(3))(2)] and [PdCl(2)(PMe(2)Ph)(2)] with elimination of tBuCl and formation of the corresponding metal(0) cyclopentaphosphene complexes [Ni{cyclo-(P(5)tBu(3))}(PEt(3))(2)] (2) and [Pd{cyclo-(P(5)tBu(3))}(PMe(2)Ph)(2)] (3). In contrast, complexes with the more labile triphenylphosphane ligand, such as [MCl(2)(PPh(3))(2)] (M=Ni, Pd), react with 1 with formation of [NiCl{cyclo-(P(5)tBu(4))}(PPh(3))] (4) and [Pd{cyclo-(P(5)tBu(4))}(2)] (5), respectively, in which the cyclo-(P(5)tBu(4)) ligand is intact. In the case of palladium, the cyclopentaphosphene complex [Pd{cyclo-(P(5)tBu(3))}(PPh(3))(2)] (6) in trace amounts is also formed. However, [Ni{cyclo-(P(5)tBu(4))}(2)] (7) is easily obtained by reaction of two equivalents of 1 and one equivalent of [NiCl(2)(bipy)] at room temperature. Complex 7 rearranges on heating in n-hexane or toluene to the previously unknown [Ni{cyclo-(P(5)tBu(4))PtBu}{cyclo-(P(4)tBu(3))}] (8), which presumably is formed via the intermediate [Ni{cyclo-(P(5)tBu(4))}{cyclo-(P(4)tBu(3))PtBu}], which, after an unexpected and unprecedented phosphanediide migration, gives 8, but always as an inseparable mixture with 7. In the reaction of 1 with [PtCl(2)(PPh(3))(2)], ring contraction and formation of [PtCl{cyclo-(P(4)tBu(3))PtBu}(PMe(2)Ph)] (9) is observed. Complexes 3-5 and 7-9 were characterised by (31)P NMR spectroscopy, and X-ray structures were obtained for 5-9.