The extent to which deuterium can act as a protecting group to prevent unwanted 1,5-hydrogen atom transfer to aryl and vinyl radical intermediates was examined in the context of the generation of α-aminoalkyl radicals in a pyrrolidine ring. Intra- and intermolecular radical trapping following hydrogen atom transfer provides an illustration of the use of the primary kinetic isotope effect in dir...

We anticipate high-valent metal–fluoride species will be highly effective hydrogen atom transfer (HAT) oxidants because of the magnitude H−F bond (in product) that drives HAT oxidation. prepared a dimeric FeIII(F)−F−FeIII(F) complex (1) by reacting [FeII(NCCH3)2(TPA)](ClO4)2 (TPA=tris(2-pyridylmethyl)amine) with difluoro(phenyl)-λ3-iodane (difluoroiodobenzene). 1 was sluggish oxidant, however, ...

This study focuses on RR, SS and RS medetomidine (MM) and inclusion of several achiral acids to distinguish which acid can help conglomerate formation instead of crystallizating racemic mixtures by defining the low-lying energy of their structures. Favorable orientation of acids was determined in interaction with the MM enantiomers after optimization. The most noticeable interactions include hy...

We optimized the geometries of the graphene and graphene with hydrogen using PW91VWN, PWCIPL,MPWLYP, G96LYP, G96141.0-210.6-310, 6-31G*Ievels of theory and compared our results with each other.We present the most important structural parameters determined for the addition of a hydrogen atom tographene and the outward movement of the carbon atom that is bonded to hydrogen is 0.48 A Also wecalcul...

Using ab initio molecular dynamics (AIMD) simulations that facilitate the treatment of rare events, we probe the active site participation in the rate-determining hydrogen transfer step in the catalytic oxidation of linoleic acid by soybean lipoxygenase-1 (SLO-1). The role of two different active site components is probed. (a) On the hydrogen atom acceptor side of the active site, the hydrogen ...

The ring size effect of macrocyclic TMC ligands in nonheme iron(IV)-oxo complexes has been examined in hydrogen atom transfer (HAT) and oxygen atom transfer (OAT) reactions; an iron(IV)-oxo complex bearing a smaller TMC ligand is more reactive in both HAT and OAT reactions, resulting from its high Fe(IV/III) redox potential.

Silicon epitaxy on hydrogen-terminated Si(001) surfaces has been studied using molecular dynamics simulations. Epitaxy on the dihydride-terminated Si(001 )-( 1 × 1) surface is inhibited for Si atoms at thermal energies due to strain hindrances created by hydrogen. At greater incident Si atom energies (2-10 eV), epitaxy proceeds primarily through "subplantation", i.e. subsurface implantation of ...

The reaction mechanisms by which antioxidants can exert their activity are: hydrogen atom transfer (HAT), proton coupled electron transfer (PCET), sequential proton loss electron transfer (SPLET), single electron transfer proton transfer (SET-PT), radical adduct formation, and sequential proton loss hydrogen atom transfer. The antioxidative activity of different compounds (flavones, flavonols, ...