In the presence of a catalytic amount of VO(acac) 2 , oxidative coupling of 2-naphthol or phenol derivatives with molecular oxygen occurred at room temperature and selectively gave the corresponding ortho-ortho coupling products in moderate to high yields.

A series of binuclear copper (Il) complexes containing a-diimine ligand has been synthesized and characterized by electron paramagnetic resonance spectroscopy. The copper complexes of the formis monodentate ligand and L is bridging ligand, were studied. The EPR spectra were recorded in solution and frozen glassy solution. In the frozen solution spectra, the values of g II are in the range of 2.10to 2.20,and theg.L are in the range of 2.03to Ul6. Furthesmore, the values of A II are in the range of 170to 188gauss, and the A.1 are in the range of 17to 32gauss.The data indicate that the structure of Cu(II) complexes is axial symmetry in square pyramidal form.

The molecular structures of binuclear copper(II) complexes [Cu2REP(μ‐OH)(ClO4)2] (4) and [Cu2REP(μ‐Cl)Cl2] (5), in which REP = deprotonated 2,6‐bis(1′‐(4′‐(2″‐pyridyl)‐2′‐thiabutyl))‐4‐methylphenol, have been characterized by single‐crystal X‐ray diffraction. The former crystallizes in the triclinic space group Pl̄ with a = 10.156(3), b = 12.631(3), c = 25.128(10) Å, α = 92.03(3), β = 96.84(3), γ = 108.02(2),° and Z − 2. Complex 5 crystallizes in the monoclinic space group C2/c with a = 12.166(2), b = 11.825(2), c = 18.240(4) Å, β = 100.97(2)°, and Z =4. All copper ions are pentacoordinated with ligation to a sulfur, a nitrogen, and the bridging phenolato oxygen of the REP ligand, the exogenous bridge, and a counteranion. The coordination geometry of each copper of the binuclear copper sites is square pyramidal in both 4 and 5. Magnetic susceptibility measurements in the temperature range 6–300 K reveal a strong antiferromagnetic spin exchange in 5 (exchange integral 2J = −460 cm−1). A diamagnetic behavior is observed for 4 according to a similar cryomagnetic investigation. The diamagnetism of 4 is further confirmed by measurements of magnetic susceptibility through Evan's method at room temperature. Complex 4 has no EPR signal. The powder EPR spectrum of 5 shows the typical triplet state characteristics with Δm = ±1 transitions at g = 2.15 and a weaker Δm = 2 transition at half field with g = 4.24.

A series of radical complexes containing manganese carbonyl, 1,3,6,8‐tetramethyl‐9,10‐phenanthroquinone (PQ1), 2,4,5,7‐tetramethyl‐9,10‐phenanthroquinone (PQ2) and triphenylphosphine are prepared and their ESR spectra are recorded and analyzed with computer simulations. From the analysis of the proton, manganese and phosphine hyperfine splitting constants, the nature of the orbital interaction and also the election transfer character are revealed. PQ1− and PQ2− Mn(CO)4 radicals are of more anion radical character than the unsubstituted PQ− Mn(CO)4 radical. The fact that the Mn and P hfsc increases and the proton hfsc decreases as the phosphine ligand increases indicated that an increasing interaction exists between the PQ pπ* and the Mn dπ orbitals with increasing phosphine number.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.