Polynuclear oxovanadium(IV) Schiff base complex [VOL2]n (L = (5-bromo-2-hydroxybenzyl-2-furylmethyl)imine): Synthesis, characterization, crystal structure, catalytic properties and thermal decomposition into V2O5 nano-particles

Syntheses, Structures, and Electrochemical Properties of Metallacyclic Oxidovanadium(V) Complexes with Asymmetric Multidentate Linking Ligands

Trinuclear metallacyclic oxidovanadium(V) complexes, [{VO(L3+2R)}3] (1-3) with asymmetric multidentate linking ligands (H3L3+2R: R = H, Me, Br), were synthesized. The molecular structure of 1 is characterized as a tripod structure, with each V(V) ion coordinated by ONO-atoms from a tridentate Schiff base site and ON-atoms from a bidentate benzoxazole site of two respective H3L3+2H ligands. The intramolecular V⋯V distances range from 8.0683 to 8.1791 Å. Complex 4 is a mononuclear dioxidovanadium(V) complex, (Et3NH)[VO2(HL3+2H)]. Cyclic voltammograms of 1-3 in DMF revealed redox couples attributed to three single-electron transfer processes.

Crystal structure of 1,1'-{(dodecane-1,12-di-yl)bis-[(aza-niumylyl-idene)methanylyl-idene]}bis-(naphthalen-2-olate)

The title compound, C34H40N2O2, exists in an extended conformation and has crystallographically imposed centrosymmetry. The crystal packing can be described as being composed of parallel layers stacked along [010]. The zwitterionic structure is stabilized by an intra-molecular N-H⋯O hydrogen-bond inter-action.

Crystal structure of (2-formyl-phenolato-κ(2) O,O')oxido(2-{[(2-oxidoeth-yl)imino]-meth-yl}phenolato-κ(3) O,N,O')vanadium(V)

In the unsymmetrical title vanadyl complex, [V(C9H9NO2)(C7H5O2)O], one of the ligands (2-formyl-phenol) is disordered over two sets of sites, with an occupancy ratio of 0.55 (2):0.45 (2). The metal atom is hexa-coordinated, with a distorted octa-hedral geometry. The vanadyl O atom (which subtends the shortest V-O bond) occupies one of the apical positions and the remaining axial bond (the longest in the polyhedron) is provided by the (disordered) formyl O atoms. The basal plane is defined by the two phenoxide O atoms, the imino-alcoholic O and the imino N atom. The planes of the two benzene rings are almost perpendicular to each other, subtending an inter-planar angle of 84.1 (2)° between the major parts. The crystal structure features weak C-H⋯O and C-H⋯π inter-actions, forming a lateral arrangement of adjacent molecules.

Synthesis, Structure, and Catalytic Epoxidation Property of a New Phenolato and μ1,1,3-Azido Co-Bridged Polynuclear Manganese(III) Complex Derived from N,N′-Bis(5-methylsalicylidene)ethane-1,2-diamine

A new phenolato and μ1,1,3-azido co-bridged polynuclear manganese(iii) complex has been synthesised and characterised. The structure of the complex has been confirmed by single crystal X-ray diffraction analyses. The ability of the complex to catalyse the epoxidation of styrene using PhIO or NaOCl as oxidant has been studied. Results show the catalysis to occur efficiently in the presence of PhIO and NaOCl.