hypervalent


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hy·per·va·lent

 (hī′pər-vā′lənt)
adj. Chemistry
Having more valences or bonds than the normal or expected number.
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Objective: The main goal of this marie sklodowska-curie (msc) application is to develop a new photocatalytic ch bond cf3-diazomethylation of aromatic rings with a new class of hypervalent iodine reagents.
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.
Reduction of Aldehydes and Imines and Reductive Amination of Aldehydes under Mild Conditions Using Hypervalent Hydridosilicates, Chem.
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.
When peroxide enters cell, it quickly reacts with heme proteins present in the cell to form hypervalent complexes, which can lead to lipid peroxidation.
A dysfunctional, hypervalent schema can also become prepotent and inhibit other schemas that are better adjusted to reality.
Examples of specific topics include nitrogen-containing organofluorine compounds through metathesis reactions, highly diastereoselective anodic fluorination, functional compounds based on hypervalent sulfur fluorides, synthesis of macrolactam marine natural products using fluorous protecting groups, solvent-peptide interaction in fluoroalcohol-water mixtures, and synthesis and conformational analysis of fluorine-containing oligopeptides.
In all complexes, both P N [pi]-bonding and the stereochemically active lone pair at phosphorus are retained, highlighting new hypervalent bonding environments for phosphorus(III).
Thottumkara (17), a senior at Macomb High School, Macomb, IL, won a silver medal and a $3,000 scholarship in the individual category for his project: "Synthesis and Oxidative Transformations Using Novel Water-Soluble Hypervalent Iodine Reagents.
As all the compounds studied in this work have so-called hypervalent phosphorus (and in some cases also sulphur) atoms, where explicit inclusion of d-orbitals in semiempirical calculations has been considered important, we also included the MNDO/d method in the current study.
For hypervalent molecules, however, the VB portrait can become complicated and computationally cumbersome.