• Journal of the Korean Chemical Society
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• v.56 no.2
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• pp.217-227
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• 2012

Syntheses of some novel oxomolybdenum(V) and dioxomolybdenum(VI) complexes with an azo dye methoxyphenolazoantipyrine (HL) derived from 4-aminoantipyrine and 2-methoxyphenol are reported. The complexes have been characterized by elemental analyses, molar conductance, magnetic susceptibility data, IR, UV-Vis, $^1H$ NMR, EPR and FAB mass spectral studies. The physicochemical studies and spectral data indicate that HL acts as a bidentate chelating ligand. The complexes have the general formulae [$MoO(HL)XCl_2$] and [$MoO_2(HL)XCl$],where X=Cl, NCS or $NO_3$. All the complexes are found to have distorted octahedral geometry. Structural and morphological characterization of the complexes [$MoO(HL)Cl_3$](1) and [$MoO_2(HL)Cl_2$](4) before and after gamma ray irradiation,was performed by X-ray diffraction and scanning electron microscopy( SEM).The ligand and the complexes were screened for their possible antimicrobial activities.

• Bulletin of the Korean Chemical Society
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• v.19 no.10
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• pp.1124-1127
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• 1998

• Journal of the Korean Chemical Society
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• v.46 no.1
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• pp.26-36
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• 2002

A solid-state reaction of $MoO_3$ with as-synthesized H-SAPO-34 generated paramagnetic Mo(V) species. The dehydration resulted in weak Mo(V) species, and subsequent activation resulted in the formation of Mo(V) species such as $Mo(V)_{5c}$ and $Mo(V)_{6c}$ that are characterized by ESR. The data of ESR and ESEM show the oxomolybdenum species, to be $(MoO_2)^+$ or $(MoO)^{3+}$. The $(MoO_2)^+$ species seems to be more probable. Since H-SAPO-34 has a low framework negative charge, $(MoO)^{3+}$ with a high positive charge can not be easily stabilized. A solution reaction between the solution of silico-molybdic acid and calcined H-SAPO-34 resulted in only $(MoO_2)^+$ species. A rhombic ESR signal is observed on adsorption of $D_2O$, $CD_3OH$, $CH_3Ch_2OD$ and $ND_3$. The Location and coordination structure of Mo(V) species has been determined by three-pulse electron spin-echo modulation data and their simulations. After the adsorption of methanol, ethylene, ammonia, and water for MoH-SAPO-34, three molecules, one molecule, one and one molecule, respectively, are directly coordinated to $(MoO_2)^+)$.

• Journal of the Korean Chemical Society
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• v.26 no.2
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• pp.73-80
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• 1982

The pyridine and 3,5-lutidine complexes of quinquevalent molybdenum have been prepared. The infrared, electronic and reflectance spectra and magnetic susceptibility data of the complexes are reported. It is found that the binuclear complexes contain the di-${\mu}$-oxo-dimolybdenum(V) group, $MoO_2Mo$, and the possible structures are proposed on the basis of elemental analysis and physical measurements.

• Journal of the Korean Chemical Society
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• v.30 no.2
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• pp.231-236
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• 1986

Oxidation of $[Mo_2O_4(C_2O_4)_2(OH_2)_2]^{2-}$ with hydrogen chromate yields the molybdenum (VI) complex, $[Mo_2O_4(C_2O_4)_2(OH_2)_2]^{2-}$. Stoichiometry for the reaction of $[Mo_2O_4(C_2O_4)_2(OH_2)_2]^{2-}$ with hydrogen chromate are expressed as ${3Mo_2}^V+2Cr^{VI}\;{\rightleftharpoons}\;{3Mo_2}_{VI}+2Cr^{III}$. Observed rate constants are dependent on $[H+]^2$. The kinetic data are consistent with a mechanism in which three successive single-electron steps convert $Cr^{VI}$to $Cr^{III}$ by way of intermediate Cr^V$ and $Cr^{IV}$. Mechanism of the reaction are presented and discussed.