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New rhenium (VII or III) complexes [ReO3(PTA)2][ReO4] (1) (PTA = l,3,5-triaza-7-phosphaadamantane), [ReO3(mPTA)][ReO4]l (2) (mPTA = N-methyl-l,3,5-triaza-7-phosphaadamantane cation), [ReO3(HMT)2] [ReO4] (3) (HMT = hexamethylenetetramine), [ReO3(n²-Tpm)(PTA)][ReO4] (4) [Tpm = hydrotris(pyrazol-l-yl)-methane, HC(Pz)3, pz = pyrazolyl], [ReO3(Hpz)(HMT)][ReO4] (5) (Hpz = pyrazole), [ReO(Tpms)(HMT)] (6) [Tpms = tris(pyrazol-lyl) methanesulfonate, O3SC(pz)3-] and [ReCl2{N2C(O)Ph}(PTA)3] (7) have been prepared from the Re(VII) oxide Re2O7 (l--6) or, in the case of 7, by ligand exchange from die benzoyldiazenido complex [ReCl2{N2C-(0)Ph}(Hpz)(PPh3)2], and characterized by IR and NMR spectroscopies, elemental analysis and electrochemical properties. Theoretical calculations at the density functional theory (DFT) level of theory indicated that the coordination of PTA to both Re(III) and Re(VII) centers by the P atom is preferable compared to the coordination by the N atom. This is interpreted in terms of the Re--PTA bond energy and hard--soft acid--base dieory. The oxo-rhenium complexes 1--6 act as selective catalysts for the Baeyer--Villiger oxidation of cyclic and linear ketones (e.g., 2-methylcyclohexanone, 2-methylcydopentanone, cydohexanone, cyclopentanone, cyclobutanone, and 3,3- dimethyl-2-butanone or pinacolone) to the corresponding lactones or esters, in the presence of aqueous H2O2 . The effects of a variety of factors are studied toward the optimization of the process. [ABSTRACT FROM AUTHOR]

The reaction between copper(II) chloride dihydrate and excess tris(1-pyrazolyl)methane results in the formation of the title complex, [Cu(C10H10N6)2]Cl2·2CH3OH. The centrosymmetric complex cation is mononuclear with octahedral coordination for Cu and two tridentate ligands. Two short and one long Cu—N distances [2.002 (3), 2.011 (2) and 2.413 (2) Å] are found, as expected for Jahn–Teller distortion. [ABSTRACT FROM AUTHOR]