Vanadium(V) Complexes of O,N,O-Donor Tridentate Ligands Containing the {VVO(OMe)}2+ Unit: Syntheses, Structures and Properties

Abstract Syntheses, characterisation and properties of two complexes containing the oxovanadium(V) methoxide unit have been described. Deprotonated benzoylhydrazones of 2–hydroxy–5–methoxy‐benzaldehyde (H2bhsOMe) and 2–hydroxy–5–chlorobenzaldehyde (H2bhsCl) were used as coligands. Crystal structures of both the complexes were determined. In solid state one of them is a dinuclear species [VO(bhsOMe)(OMe)]2 (1) whereas the other one is a mononuclear complex [VO(bhsCl)(OMe)(HOMe)](2). The dinegative ligands coordinate the metal ions via phenolate–O, imine–N and deprotonated amide–O atoms. In 1, the metal ions of two square pyramidal VO(bhsOMe)(OMe) units share the methoxide groups to form a dinuclear species. The oxygen of a methanol molecule completes the hexacoordination of the metal centre in 2. In each of the two distorted octahedral VO5N moieties of 1 the bridging methoxide oxygen and in that of 2 the methanol oxygen is trans to the corresponding oxo group. Both the complexes are redox active. The VO3+ to VO2+ reduction potentials (vs Ag/AgCl) of 1 and 2 are observed at −0.25 and −0.04 V, respectively. The band positions in the electronic spectra and the redox potentials reflect the influence of the substituents present on the ligands.

[1]  A. Choudhury,et al.  SYNTHESIS, STRUCTURE AND PROPERTIES OF MANGANESE(II) COMPLEXES WITH AROYLHYDRAZONES OF 2-PYRIDINE-CARBOXALDEHYDE , 1999 .

[2]  H. Gray,et al.  Aerobic Epoxidation of Olefins Catalyzed by Electronegative Vanadyl Salen Complexes. , 1997, Inorganic chemistry.

[3]  S. P. Rath,et al.  Chemistry of hydrazonato oxovanadium(V) alkoxides derived from dihydric/monohydric alcohols , 1997 .

[4]  S. Pal,et al.  IRON(III) COMPLEXES OF N-BENZOYL-N /−SALICYLIDENEHYDRAZINES: SYNTHESIS, CHARACTERIZATION AND PROPERTIES , 1997 .

[5]  D. J. Price,et al.  Biomimetic control of iron oxide and hydroxide phases in the iron oxalate system , 1997 .

[6]  A. Powell.  Polyiron oxides, oxyhydroxides and hydroxides as models for biomineralisation processes , 1997 .

[7]  C. Rao,et al.  Alkoxo Bound Monooxo- and Dioxovanadium(V) Complexes: Synthesis, Characterization, X-ray Crystal Structures, and Solution Reactivity Studies. , 1996, Inorganic chemistry.

[8]  Stephen Mann,et al.  Synthesis of inorganic materials with complex form , 1996, Nature.

[9]  X. You,et al.  Synthesis, characterization and crystal structure of a binuclear cis-dioxovanadium(V) schiff base complex , 1996 .

[10]  Wei Wang,et al.  A study of an oxovanadium(V) complex with a tridentate schiff base ligand , 1996 .

[11]  R. Harlow,et al.  Phosphatovanadium chemistry: Behavior of phosphato groups covalently bound to only one vanadyl center , 1996 .

[12]  P. Matias,et al.  Crystal and molecular structure of [V2O3(sal-L-val)2(H2O)](sal-L-val =N-salicylidene-L-valinate) and spectroscopic properties of related complexes , 1996 .

[13]  S. P. Rath,et al.  Chemistry of oxovanadium(V) alkoxides: synthesis and structure of mononuclear complexes incorporating ethane-1,2-diol , 1996 .

[14]  S. Mondal,et al.  Chemistry of VO 3+ and VO 2+ complexes incorporating N-salicylidene-α-aminoacidates , 1995 .

[15]  S. Mondal,et al.  Synthesis and structure of carboxyl-bonded oxovanadium(V) complexes incorporating α-amino acid salicylaldiminates and quinolin-8-olate , 1995 .

[16]  D. Rehder,et al.  [VO{N-(2-oxido-1-naphthylmethylene)-L-ala}OBus(HOBus)]: characterization of a complex containing four centres of chirality , 1995 .

[17]  E. Ludwig,et al.  Komplexe von Vanadium und Titan mit 2,2′‐Dihydroxyazobenzen. Kristallstrukturen von 2,2′‐Dihydroxyazobenzenato(2‐)‐oxo‐methoxo‐methanol‐vanadium(V) und μ‐Oxo‐bis[2,2′‐dihydroxyazobenzenato(2‐)‐oxo‐vanadium(V)] , 1994 .

[18]  A. Butler,et al.  Oxovanadium(V) alkoxo-chloro complexes of the hydridotripyrazolylborates as models for the binding site in bromoperoxidase , 1994 .

[19]  T. Hirao,et al.  A novel regioselective ring-opening oxidation of cyclobutenones with VO(OEt)Cl2 , 1994 .

[20]  S. Dutta,et al.  Synthesis, structure and metal redox of new VO3+ and VO2+ complexes incorporating mixed tridentate–bidentate binding , 1994 .

[21]  A. Butler,et al.  Biomimics of vanadium bromoperoxidase : vanadium(V)-schiff base catalyzed oxidation of bromide by hydrogen peroxide , 1993 .

[22]  K. Dehnicke,et al.  Vanadium‐Komplexe mit dreizähnigen diaciden Liganden. Die Kristallstrukturen von Bis[acetylacetonthiobenzoylhydrazonato(2‐)]vanadium(IV), Methoxo‐oxo‐[salicylaldehydthiobenzoylhydrazonato(2‐)]vanadium(V) und Methoxo‐oxo‐[salicylaldehydbenzoylhydrazonato(2‐)]methanolvanadium(V) , 1992 .

[23]  D. Rehder,et al.  Tris(cyclopentanolato)oxovanadium(V): a Model for the Transition State of Enzymatic Phosphoester Cleavage , 1992 .

[24]  R. Felty,et al.  Cyclic vanadium(V) alkoxide. An analog of the ribonuclease inhibitors , 1991 .

[25]  D. Crans,et al.  Interaction of trace levels of vanadium(IV) and vanadium(V) in biological systems , 1989 .

[26]  K. Nakajima,et al.  Crystal Structures of [VO(sal-L-ala)(OCH3)(CH3OH)] (sal-L-ala=N-salicylidene-L-alaninate) and {[VO(sal-L-ala)]2O}2·2CH2Cl2, and the Catalytic Activity of These and Related Complexes on Asymmetric Oxidation of Methyl Phenyl Sulfide with t-Butyl Hydroperoxide , 1989 .

[27]  V. Pecoraro,et al.  Vanadium complexes of the tridentate Schiff base ligand N-salicylidene-N'-(2-hydroxyethyl)ethylenediamine: acid-base and redox conversion between vanadium(IV) and vanadium(V) imino phenolates , 1988 .

[28]  Richard H. Holm,et al.  Metal-centered oxygen atom transfer reactions , 1987 .

[29]  R. Wever,et al.  Vanadium(V) as an essential element for haloperoxidase activity in marine brown algae: purification and characterization of a vanadium(V)-containing bromoperoxidase from Laminaria saccharina , 1986 .

[30]  E. Tiekink,et al.  Structures of 2 Vanadium(V) Complexes With Tridentate Ligands , 1986 .

[31]  M. Gresser,et al.  Interaction of inorganic vanadate with glucose-6-phosphate dehydrogenase. Nonenzymic formation of glucose 6-vanadate. , 1985, The Journal of biological chemistry.

[32]  L. Que,et al.  Model studies of iron―tyrosinate proteins , 1985 .

[33]  S. Pal,et al.  Stabilisation of copper(I) by an azoimine ligand: redox properties and reactions of bis(phenylazoacetaldoximato)bis(phenylacetaldoxime)dicopper(I) , 1985 .

[34]  R. Mukherjee,et al.  Electron transfer in groups of iron, cobalt, and copper triazene 1-oxides: Hammett correlation, ligand redistribution, and crystal field effects , 1982 .

[35]  K. Nakamoto.  Infrared and Raman Spectra of Inorganic and Coordination Compounds , 1978 .

[36]  L. Sayed,et al.  Coordination compounds of hydrazine derivatices with transition metals—XIX , 1974 .

[37]  R. J. Williams,et al.  The absorption spectra of some complex ions of analytical importance , 1955 .

[38]  L. Sacconi.  Komplexchemische Reaktionen. V. Mehrkernige Nickel‐Innerkomplexe mit Acylhydrazonen von α‐ und β‐Diketonen , 1954 .

[39]  G. Struve.  21. Th. Curtius: Hydrazide und Azide organischer Säuren II. Abhandlung. Ueber Benzhydrazid , 1894 .