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A new oxidovanadium(V) complex, [VOL(OEt)(EtOH)] (1), and a new dioxidomolybdenum(VI) complex, [MoO2L(OH2)] (2), where L is the dianionic form of 2-bromo-N'-(3,5-dichloro-2-hydroxybenzylidene)benzohydrazide, have been synthesized and structurally characterized by physico-chemical methods and single crystal X-ray determination. X-ray analysis indicates that the V and Mo ions in the complexes are in octahedral coordination. Crystal structures of the complexes are stabilized by hydrogen bonds. The catalytic property for epoxidation of styrene by the complexes was evaluated. Both complexes have effective catalytic properties for the epoxidation of styrene, with conversions over 76% and selectivities over 92%. [ABSTRACT FROM AUTHOR]

A novel binuclear oxidovanadium(V) complex [V2O2(μ-O)L2(OEt)2], where L is the deprotonated form of 2,4-dibromo-6-(5-methylamino-[1,3,4]thiadiazol-2-yl)phenol (HL), was prepared by the reaction of 2-(3,5-dibromo-2-hydroxybenzylidene)-N-methylhydrazinecarbothioamide (HL') and VO(acac)2 in ethanol. The ligand L' underwent a cyclization during the coordination, to form a new ligand L. Structure of the complex was characterized by physicochemical methods and single-crystal X-ray determination. Crystal of the complex crystallizes in hexagonal space group R-3, with a = b = 33.302(3) Å, c = 15.308(2) Å, α = β = 90°, γ = 120°, V = 14702(3) Å3, Z = 18, R1 = 0.0823, wR2 = 0.2064, S = 1.011. X-ray analysis indicates that the V atom in the complex is in an octahedral coordination environment, constructed by the phenolate O and thiadiazol N atoms of L, one oxido O atom, one bridging O atom, and one deprotonated ethanol O atom. The distance between the two V atoms is 3.365(1) Å. The complex has an effective catalytic property for the oxidation of several olefins. [ABSTRACT FROM AUTHOR]

A new manganese(II) complex [MnL2(NCS)2]·2H2O with the Schiff base ligand derived from 3-bromosalicylaldehyde withN-cyclohexylpropane-1,3-diamine has been synthesized and structurally characterized by physicochemical methods and single-crystal X-ray determination. The crystal of the complex crystallizes in monoclinic space groupC2/c, witha= 24.749(2),b= 7.2957(7),c= 26.183(4) Å,β= 118.70(2)°,V= 4171.6(8) Å3,Z= 4,R1= 0.0893,wR2= 0.2305, GOOF = 1.084. X-ray analysis indicates that the complex is a mononuclear manganese species, which possesses crystallographic inversion center symmetry. The Mn atom, lying on the inversion center, is coordinated in an octahedral coordination by two phenolate O and two imine N atoms from two Schiff base ligands, and two thiocyanate N atoms. The catalytic property for epoxidation of styrene by the complex has also been tested. [ABSTRACT FROM PUBLISHER]

Two new dioxomolybdenum(VI) complexes [MoO2(Bhbz) (CH3OH)] (1) and [MoO2(Cnbz)(CH3OH)] (2) with the benzohydrazone ligands H2Bhbz and H2Cnbz derived from 5-chlorosalicylaldehyde with 4-nitrobenzohydrazide and 3-bromosalicylaldehyde with 2-hydroxybenzohydrazide, respectively, have been synthesized and structurally characterized by physicochemical methods and single crystal X-ray determination. The crystal of (1) crystallizes in triclinic space groupP-1, witha= 8.0014(9),b= 9.6294(10),c= 11.4204(12) Å,α= 89.193(2),β= 87.833(2),γ= 89.110(2)°,V= 879.11(16) Å3,Z= 2,R1= 0.0464,wR2= 0.1185,S= 1.051. The crystal of (2) crystallizes in monoclinic space groupP21/c, witha= 7.4108(3),b= 18.7901(7),c= 12.6293(5) Å,β= 104.4850(10)°,V= 1702.72(12) Å3,Z= 4,R1= 0.0236,wR2= 0.0576,S= 1.061. X-ray analysis indicates that the structures of both complexes are similar to each other. The molybdenum atom in each complex is in an octahedral coordination environment, constructed by two oxo groups and NO2donor set of the ligand, and one methanol O atom. The complexes have effective catalytic property for the oxidation of several olefins. [ABSTRACT FROM PUBLISHER]

Two new dioxomolybdenum(VI) complexes, [MoO2 (Cinh)(CH3OH)] (1) and [MoO2(Minh)(CH3OH)] (2), with the isonicotinohydrazone ligands H2Cinh and H2Minh derived from isonicotinohydrazide with 5-chlorosalicylaldehyde and 3-methoxysalicylaldehyde, respectively, have been synthesized and structurally characterized by physico-chemical methods and single crystal X-ray determination. The crystal of (1) crystallizes in triclinic space group P-1, with a = 6.553(2), b = 10.737(4), c = 12.907(4) Å, α = 68.021(2), β = 83.788(3), γ = 75.072(3)°, V = 813.6(5) Å3, Z = 2, R1 = 0.0291, wR2 = 0.0617, S = 1.044. The crystal of (2) crystallizes in monoclinic space group P21/n, with a = 6.792(2), b = 30.259(4), c = 7.920(3) Å, β = 93.703(3)°, V = 1624.3(8) Å3, Z = 4, R1 = 0.0501, wR2 = 0.1250, S = 1.087. X-ray analysis indicates that the structures of both complexes are similar to each other. The molybdenum atom in each complex is in an octahedral coordination environment, constructed by two oxo groups and NO2 donor set of the isonicotinohydrazone ligand, and one methanol O atom. [ABSTRACT FROM AUTHOR]