geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Vanadium-induced formation of thiadiazole and thiazoline compounds. Mononuclear and dinuclear oxovanadium(v) complexes with open-chain and cyclized thiosemicarbazone ligands


, : Vanadium-induced formation of thiadiazole and thiazoline compounds. Mononuclear and dinuclear oxovanadium(v) complexes with open-chain and cyclized thiosemicarbazone ligands. Dalton Transactions: 9914-9923

Reactions of the salicylaldehyde 4-phenylthiosemicarbazone (H(2)L) with selected vanadium(iv) and vanadium(v) precursors ([VO(acac)(2)], [VO(OAc)(2)], VOSO(4), [V(2)O(4)(acac)(2)]) were investigated under aerobic conditions in different alcohols (methanol, ethanol, propanol). In all examined cases mononuclear alkoxo vanadium(v) complexes [VOL(OR)] (1) (OR = OMe, OEt, OPr) were isolated as major products. On prolonged standing, mother liquids afforded dinuclear vanadium(v) complexes [V(2)O(3)(L(cycl))(2)(OR)(2)] (3) (OR = OMe, OEt, OPr), where L(cycl)(-) represents 1,3,4-thiadiazole ligand, formed by vanadium-induced oxidative cyclization of H(2)L. When [VO(acac)(2)] or [V(2)O(4)(acac)(2)] were used as precursors, in addition to products 1 and 3, a thiazoline derivative HL(acac)(cycl) (2) was isolated. This compound, formed by a reaction between acetylacetone and H(2)L, represented the second type of cyclic product. The products were characterized by IR and NMR spectroscopies, TG analysis, and in some cases by single-crystal X-ray diffraction. To the best of our knowledge, compounds [V(2)O(3)(L(cycl))(2)(OR)(2)] represent the first structurally characterized dinuclear vanadium(v) complexes with a thiadiazole moiety acting as a bridging ligand. Complexes 1 and 3, when dissolved in an appropriate alcohol, underwent substitution of the alkoxo ligand as confirmed by XRPD. The kinetics of reactions in methanolic solutions was qualitatively studied by UV-Vis and ESMS spectrometries. Under the experimental conditions applied, a relatively slow formation of the mononuclear complex [VOL(OMe)] and an even slower formation of the cyclic species 2 were observed, whereas the presence of dinuclear compound [V(2)O(3)(L(cycl))(2)(OMe)(2)] in the reaction mixture could not be detected.

US$19.90

PMID: 19885541

DOI: 10.1039/b913653c


Other references

Monga, G.; Bonfanti, S.; Bussolati, G., 1974: Cholin esterase rich cells in the rat fundic mucosa a light microscopic and electron microscopic investigation. Histochemical Journal 6(5): 559-565

Liu, Y.; Wang, H-Qing., 2006: Modelling a penicillin fed-batch fermentation using least squares support vector machines. The biochemical processes are usually characterized as seriously time varying and nonlinear dynamic systems. Building their first-principle models are very costly and difficult due to the absence of inherent mechanism and efficient on-line sensors...

Bergerud, A.T.; Butler, H.E., 1985: Aggressive and spacing behavior of female Blue Grouse. Female blue grouse (D. obscurus) on Stuart Island, Washington [USA] were found to interact aggressively with female dummies in the prelaying period when a taped cackle call was played. Interactions included tail fanning, wing dragging, everting th...

Read, A.T.; Govind, C.K., 1998: Cell types in regenerating claws of the snapping shrimp, Alpheus heterochelis. Cell types in the regenerating claws of adult snapping shrimps, Alpheus heterochelis, are described, based on electron microscopy. Following autotomy of a limb, the coxal stump is secured by a membrane lined by a layer of proliferating epithelial...

Fidanza, F.; Cioffi, L.A., 1959: Method for the separation and determination of lipoproteins of the serum by means of electrophorsis on a starch block. Bollettino Della Societa Italiana di Biologia Sperimentale 35: 1901-1903

Fink, L.D.; Akiyama, J., 1952: Response of the excised guinea pig tracheal muscle to morphine and meperidine. Morphine in a concn. of 2.0 m[image] per liter produces muscular contractions of the excised guinea pig tracheal tube approximately one-third of those obtained with 0.001 m[image] of acetylcholine; meperidine has no effect. Morphine increases the...

Miller, M.Craig., 2007: Compulsive buying. Harvard Mental Health Letter 23(7): 8-8

Tan, S.D.; Kuijpers-Jagtman, A.M.; Semeins, C.M.; Bronckers, A.L.J.J.; Maltha, J.C.; Von-Den-Hoff, J.W.; Everts, V.; Klein-Nulend, J., 2006: Fluid shear stress inhibits TNF alpha-induced osteocyte apoptosis. Bone tissue can adapt to orthodontic load. Mechanosensing in bone is primarily a task for the osteocytes, which translate the canalicular flow resulting from bone loading into osteoclast and osteoblast recruiting signals. Apoptotic osteocytes att...

Grigsby K.N.; Kerley M.S.; Paterson J.A.; Daume S.R., 1992: Ruminal carboxymethyl cellulase activity by steers fed soybean hull and corn based energy supplements. Journal of Animal Science 70(SUPPL 1): 91

Marín-Franch, Ián.; Swanson, W.H.; Adams, B.R.; Zhu, H.; Crabb, D.P., 2013: Novel analytical methods for stratus OCT: alignment of the scan circle. Measurement of retinal nerve fiber layer (RNFL) thickness using optical coherence tomography (OCT) is commonly used in the detection and management of glaucoma. The Stratus OCT (Carl Zeiss Meditec, Inc., Dublin, CA) is widely used, but image acqui...