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The preparation of neutral V(II) aryloxides has been achieved via ligand-replacement reactions on three V(II) complexes (Mz2V(py))2(mu-N2), Mz2V(py)2, and VCl2(TMEDA)2 (Mz = o-Me2NCH2C6H4, TMEDA = N,N,N'N',-tetramethylethylenediamine) with several phenols, or their corresponding alkali salts. In the case of sterically demanding phenols [2,6-(t-Bu)2-4-MeC6H2OH, 2,6-Ph2PhOH, 2-(MeO)C6H4OH] it was possible to isolate and characterize monomeric and neutral V(II) aryloxides with a variety of coordination geometries. When similar reactions were carried out on the same complexes with less bulky alcohols (2,6-Me2PhOH, PhOH, t-BuOH), monomeric V(III) and dimeric V(III)/V(IV) mixed-valence species were isolated. The crystal structures of the square-planar [2,6-(t-Bu)2-4-MeC6H2O]2V(py)2 (4), saddle-shape (2,6-Ph2PhO)2V(TMEDA) (5), square-pyramidal (2,6-Ph2PhO)2V(py)3 (6), and octahedral [2-(MeO)C6H4O]2V(TMEDA) (7) were demonstrated by X-ray diffraction analysis. Crystal data are as follows. 4: C40H56VN2O2.(C7H8)2, M(r) = 833.12, triclinic, P1BAR, a = 9.701(2) angstrom, b = 15.303(3) angstrom, c = 9.000(2) angstrom, alpha = 101.99(2)degrees, beta = 112.59(2)degrees, gamma = 74.20(2)degrees, V = 1179.0(4) angstrom3, Z = 1, lambda = 0.710 69 angstrom, R = 0.053, R(w) = 0.068, and GoF = 2.89 for 365 parameters and 3475 out of 4134 unique reflections. 5: C42H42N2O2V, M(r) = 657.74, monoclinic, P2(1)/a, a = 16.373(1) angstrom, b = 11.1624(9) angstrom, c = 19.536(3) angstrom, beta = 97.35(1)degrees, V = 3541.3(7) angstrom3, Z = 4, lambda = 0.709 30 angstrom, R = 0.044, R(w) = 0.017, and GoF = 1.63 for 589 parameters and 2714 out of 4603 unique reflections. 6: C51H41N3O2V, M(r) = 778.85, monoclinic, C2/c, a = 20.65(2) angstrom, b = 14.28(1) angstrom, c = 16.08(1) angstrom, beta = 119.89(7)degrees, V = 4113(7) angstrom3, Z = 4, R = 0.053, R(w) = 0.049, and GoF = 1.34 for 259 parameters and 1505 out of 3182 unique reflections. 7: C20H30VN2O4, M(r) = 413.41, orthorhombic, Pna2(1), a = 13.519(5) angstrom, b = 13.846(4) angstrom, c = 11.196(2) angstrom, V = 2096(1) angstrom3, Z = 4, R = 0.037, R(w) = 0.047, and GoF = 1.96 for 244 parameters and 1669 out of 2116 unique reflections. Reaction of 7 with (Me3Si)CHN2 gave the new diamagnetic and dinuclear complex {[2-(MeO)C6H4O]2V}2[mu-NNCH-(SiMe3)]2 (13). Complex 13 was co-crystallized in a 1/1 ratio with {[2-(MeO)C6H4O]2V}2[mu-OC6H4(2-OCH3)]2, which was formed from the thermal degradation of 13 through a complicated reaction. Crystal data for the co-crystallite {[2-MeO)C6H4O]2V}2[mu-NNCH(SiMe3)]2/{[2-MeO)C6H4O]2V}2[mu-OC6H4(2-OCH3)]2 (14) are as follows. 14: C39H45V2N2O10Si, M(r) = 831.76, triclinic, P1BAR, a = 14.443(6) angstrom, b = 15.039(6) angstrom, c = 10.679(3) angstrom, alpha = 100.66(3)degrees, beta = 97.46(3)degrees, gamma = 113.84(3)degrees, V = 2030(1) angstrom3, Z = 2, R = 0.045, R(w) = 0.060, and GoF = 2.45 for 488 parameters and 5530 out of 6946 unique reflections.

The preparation of neutral V(II) aryloxides has been achieved via ligand-replacement reactions on three V(II) complexes (Mz2V(py))2(mu-N2), Mz2V(py)2, and VCl2(TMEDA)2 (Mz = o-Me2NCH2C6H4, TMEDA = N,N,N'N',-tetramethylethylenediamine) with several phenols, or their corresponding alkali salts. In the case of sterically demanding phenols [2,6-(t-Bu)2-4-MeC6H2OH, 2,6-Ph2PhOH, 2-(MeO)C6H4OH] it was possible to isolate and characterize monomeric and neutral V(II) aryloxides with a variety of coordination geometries. When similar reactions were carried out on the same complexes with less bulky alcohols (2,6-Me2PhOH, PhOH, t-BuOH), monomeric V(III) and dimeric V(III)/V(IV) mixed-valence species were isolated. The crystal structures of the square-planar [2,6-(t-Bu)2-4-MeC6H2O]2V(py)2 (4), saddle-shape (2,6-Ph2PhO)2V(TMEDA) (5), square-pyramidal (2,6-Ph2PhO)2V(py)3 (6), and octahedral [2-(MeO)C6H4O]2V(TMEDA) (7) were demonstrated by X-ray diffraction analysis. Crystal data are as follows. 4: C40H56VN2O2.(C7H8)2, M(r) = 833.12, triclinic, P1BAR, a = 9.701(2) angstrom, b = 15.303(3) angstrom, c = 9.000(2) angstrom, alpha = 101.99(2)degrees, beta = 112.59(2)degrees, gamma = 74.20(2)degrees, V = 1179.0(4) angstrom3, Z = 1, lambda = 0.710 69 angstrom, R = 0.053, R(w) = 0.068, and GoF = 2.89 for 365 parameters and 3475 out of 4134 unique reflections. 5: C42H42N2O2V, M(r) = 657.74, monoclinic, P2(1)/a, a = 16.373(1) angstrom, b = 11.1624(9) angstrom, c = 19.536(3) angstrom, beta = 97.35(1)degrees, V = 3541.3(7) angstrom3, Z = 4, lambda = 0.709 30 angstrom, R = 0.044, R(w) = 0.017, and GoF = 1.63 for 589 parameters and 2714 out of 4603 unique reflections. 6: C51H41N3O2V, M(r) = 778.85, monoclinic, C2/c, a = 20.65(2) angstrom, b = 14.28(1) angstrom, c = 16.08(1) angstrom, beta = 119.89(7)degrees, V = 4113(7) angstrom3, Z = 4, R = 0.053, R(w) = 0.049, and GoF = 1.34 for 259 parameters and 1505 out of 3182 unique reflections. 7: C20H30VN2O4, M(r) = 413.41, orthorhombic, Pna2(1), a = 13.519(5) angstrom, b = 13.846(4) angstrom, c = 11.196(2) angstrom, V = 2096(1) angstrom3, Z = 4, R = 0.037, R(w) = 0.047, and GoF = 1.96 for 244 parameters and 1669 out of 2116 unique reflections. Reaction of 7 with (Me3Si)CHN2 gave the new diamagnetic and dinuclear complex {[2-(MeO)C6H4O]2V}2[mu-NNCH-(SiMe3)]2 (13). Complex 13 was co-crystallized in a 1/1 ratio with {[2-(MeO)C6H4O]2V}2[mu-OC6H4(2-OCH3)]2, which was formed from the thermal degradation of 13 through a complicated reaction. Crystal data for the co-crystallite {[2-MeO)C6H4O]2V}2[mu-NNCH(SiMe3)]2/{[2-MeO)C6H4O]2V}2[mu-OC6H4(2-OCH3)]2 (14) are as follows. 14: C39H45V2N2O10Si, M(r) = 831.76, triclinic, P1BAR, a = 14.443(6) angstrom, b = 15.039(6) angstrom, c = 10.679(3) angstrom, alpha = 100.66(3)degrees, beta = 97.46(3)degrees, gamma = 113.84(3)degrees, V = 2030(1) angstrom3, Z = 2, R = 0.045, R(w) = 0.060, and GoF = 2.45 for 488 parameters and 5530 out of 6946 unique reflections.

Novel biomimetic, aerobic oxidation with an organocatalyst was performed. The oxidations of organic substrates such as sulfides, secondary amines, N-hydroxylamines, and tertiary amines with molecular oxygen (1 atm) or even in air in the presence of 5-ethyl-3-methyllumiflavinium perchlorate catalyst and hydrazine monohydrate in 2,2,2-trifluoroethanol occur highly efficiently to give the corresponding oxidized compounds in excellent yields along with water and molecular nitrogen, which are environmentally benign. The TON of the oxidation of sulfides amounts to 19 000.

La cinetique et les constantes d'equilibre pour le transfert d'azote a travers des membranes constituees par un copolymere de methacrylate d'octyle et d'un complexe de manganese sont determinees