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adj. Chemistry
Having more valences or bonds than the normal or expected number.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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Quite a significant amount of literature is available for bromination protocols of methylarylketonesthat involve use of: Br2 or its complexes in the presence of protic or Lewis acid,[5-11]bases,[12-15]N-bromosuccinimide (NBS),[16-22]NBS/NH4OAc,[23]a combination of N-halosuccinimide/TsOH/CH3CN,[24] hypervalent iodine sulfonate/magnesium halides under microwaves[25]and HBr/O2/hv.[26]Nevertheless, these brominating reagents have some limitations including their low atom efficiency, the need for reagent residue removal and that molecular bromine is required for their preparation.The regioselectivityand mono-halogenation of ketones are still problems that have not been solved.[27-32]
Reduction of Aldehydes and Imines and Reductive Amination of Aldehydes under Mild Conditions Using Hypervalent Hydridosilicates, Chem.
To synthesize bis- and tris-cylcometalated platinum(IV) complexes, cyclometalated platinum(II) pendant complexes will be oxidized using hypervalent iodine reagents followed by ligand substitution.
The efficiency of several hypervalent iodine (III) compounds as oxidants has already been reported by Rattanangkool et al.
Among the topics are analytic methods of iodine and iodides, ion chromatography, hypervalent iodine, iodine production from oilfield brine, iodinating reagents, chemical reactions mediated by metal iodides, synthetic thyroid hormone, iodine deficiency disorders and their correction using iodized salt and/or iodine supplements, iodine in polymer synthesis, iodine in dye-sensitized solar cells, and the atmospheric chemistry of iodine.
The paper titled "The impact of conservation on the status of the world's vertebrates" published in Science is the highest cited paper which has been cited 283 times followed by "2-Iodoxybenzoic acid (IBX): An efficient hypervalent iodine reagent" by Satam, V.
Sadler, "A Neutral spirocyclic hexacoordinated germanium(IV) complex: hypervalent germanium compounds with sulfur-containing eight-membered rings," Inorganic Chemistry, vol.
Yang, "Utilization of hypervalent iodine in organic synthesis: a novel and facile two-step protocol for the synthesis of new derivatives of 1H-imidazo[1,2-b] pyrazole by the cyclocondensation involving a-tosyloxyacetophenones," Journal of Heterocyclic Chemistry, vol.
Skibsted, "Kinetics of reduction of hypervalent iron in myoglobin by crocin in aqueous solution," Free Radical Research, vol.
When peroxide enters cell, it quickly reacts with heme proteins present in the cell to form hypervalent complexes, which can lead to lipid peroxidation.
First, the model posits that when a schema becomes rigid and dysfunctional, it becomes hypervalent, or easily activated by a trivial stimulus.