Single 1,2-migration reaction

In a series of papers, Ohashi and co-workers have used single crystal neutron diffraction to characterize the products of hydrogen(deuterium)-migration reactions that accompany isomerization of certain reactive ligands bound to bis(dimethylglyoximato)cobalt moieties upon UV irradiation, remarkably in single-crystal-to-single-crystal transfor-... 

Mass transport in an electrochemical reactor occurs by three mechanisms migration in the electrical field, film diffusion, and convection. The first of these is a special feature of electrochemical reactions, whereas the other two are common to all reactions that have a solid phase. However, where an inertsupporting electrolyte is used, the effect of migration can be neglected. With this assumption, let us consider a single electrode reaction given by reaction 21.3. When a finite current is passed through the cell and conditions are perfectly reversible, the concentration overpotential can be expressed as (Pickett, 1979)... 

MINDO/3 calculations [54,100] have shown that in the case of 1,4-diotropic proton migrations, such as XXIIIa XXIIIb, XXIVa XXIVb,XXVa XXVb, the products of the single migration XXIIIc, XXIVc, XXVc correspond, contrary to expectations, to the minima on the PES. Thus, these reactions are characterized by a stepwise mechanism, which can be accounted for by unfavorable stereochemistry of the reactive site and by the reaction centers being spaced fairly wide apart. 

A single isomer of 4-phcnylpcrhydropyrido[2,1 -t][l,4]oxazin-l-one 436 was isolated from a reaction mixture of 2-bromocyclohexane and 2-azido-2-phenylethanol (Scheme 37). The formation of 436 was presumed to be from azepino[l,2-A [l,3]oxazole intermediate 435 by HBr elimination and 1,2-migration <2000JOC3771>. 

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