Search

The formation of sulfinybicyclo[4.2.0]octan-1-ols from the lithium enolate of cyclohexanone with (plusmn)-phenyl vinyl sulfoxide or (R)-(+)-p-tolyl vinyl sulfoxide is used to probe the mode of a novel cyclization reaction. Using phenyl vinyl sulfoxide, variations in the reaction lighting and solvent are investigated, in conjunction with radical trapping (TEMPO) and isotope labeling (deuterium) experiments.

The ruthenium(II) complex, [Ru[Cl.sub.2](NO)L] (I), (L = [[(2-py).sub.2]P[C.sub.2][H.sub.4]P[O.sub.2](2-py)]-) was obtained from recrystallization of Ru[Cl.sub.3]NO(d2pype) (d2pype = [(2-py).sub.2]P[C.sub.2][H.sub.4]P[(2-py).sub.2]) in the presence of HN[O.sub.3], crystallizing in the monoclinic space group [P2.sub.1] (no. 4), with a = 8.012(4) [Angstrom], b = 14.454(4) [Angstrom], c = 9.353(3) [Angstrom], [beta] = 105.77(3)[degrees], and Z = 2. Crystals of the DMSO solvate of the complex (II) were obtained from [(C[D.sub.3]).sub.2]SO solution, crystallizing in the monoclinic space group [P2.sub.1]/c (no.14) with a = 9.7080(2) [Angstrom], b = 22.2920(5) [Angstrom], c = 11.5230(3) [Angstrom], [beta] = 92.0450(10)[degrees], and Z = 4. In both complexes, the geometry about the ruthenium atom is a distorted octahedron mainly as a result of the tridentate [P,N,O]-bonding mode of L. The v (NO) bands at 1875 [cm.sup-1] in both complexes are consistent with the linear disposition of the NO group and the Ru atom as is observed in the X-ray crystal structure (Ru-N1-O1 angle = 178.5(4)[degrees]). Key words: pyridylphosphine, nitrosyl, ruthenium complex, X-ray structure.

The reaction between tris(2,4,6-trimethoxyphenyl)phosphine (TMPP) and Cu(I) iodide in acetonitrile yields 1:1 complexes. The mole ratio of the reactants influences the structures of the complexes. Room-temperature single-crystal X-ray studies help analyze the structure of the 1:1 molecular adduct ((TMPP)CuI) from a reaction between TMPP and CuI in a 1:2 ratio. The complex has mononuclear ((TMPP)CuI) molecules that have linear two-coordination about the copper atom. 31 P NMR and IR studies reveal the formation of a different 1:1 complex by a reaction between TMPP and CuI in a 1:1 ratio.

The synthesis of (tris(2,4,6-trimethoxyphenyl)phosphine)AgX, where X = Cl, Br and I, by the reaction of the phosphine ligand with AgX was undertaken. (TMPP)AgCl and (TMPP)AgBr were found to be isomorphous with each other, were monomeric, and possessed a silver atom residing in an almost linear two-coordinate environment. Both complexes also contained the P-Ag-X fragment. Moreover, the far-infrared spectra of the complexes showed strong bands at 282 cm(super -1) for (TMPP)AgCl and 215 cm(super -1) for (TMPP)AgBr.

Research was conducted to examine the structures of three novel, weakly cytotoxic tetraphenolic bis-spiroketals, prunolides A, B and C, by isolating them as well as the known ascidian antibiotic, rubrolide A. Results demonstrate that the prunolides represent a structurally novel family of ascidian metabolites. Findings also indicate that the prunolides may possibly arise from an oxidative dimerization of a rubrolide precursor.

Research was conducted to examine the coordination chemistry of copper(I) with PBz3. Results were based on the X-ray structure determination of the complex and a comparison of the solid-state 31P CPMAS NMR parameters of (Cu(PBz3)2)(CuBr2) and (Cu(PBz3)2)PF6 with the ones derived from a range of other two-, three- and four-coordinate copper(I) phosphine complexes. Findings reveal that bis(tribenzylphosphine)copper(I) salts preferentially form two-coordinate linear 'CuP2' complexes.

The article describes the synthesis and characterization of a series of ionic Ru(II) arene Cp* sandwich complexes. The results from screening for cytotoxicity against a range of human tumor cell lines and normal human cells reveal the complexes to exhibit promising anticancer activity that varies with changes in the arene ligand and the anionic counterion.

An efficient formal synthesis of (plusmn)-hyphodermin B was achieved from a diketone in six steps and 15% overall yield. The synthesis was developed without the need for complex protection-deprotection strategies and exploited the unexpected regioselective reduction of the anhydride.