Ordering intramolecular

The reverse reaction (formation of metal alkyls by addition of alkenes to M-H) is the basis of several important catalytic reactions such as alkene hydrogenation, hydroformylation, hydroboration, and isomerization. A good example of decomposition by y3-elimination is the first-order intramolecular reaction ... 

Spectrophotometry has been a popular means of monitoring redox reactions, with increasing use being made of flow, pulse radiolytic and laser photolytic techniques. The majority of redox reactions, even those with involved stoichiometry, have seeond-order characteristics. There is also an important group of reactions in which first-order intramolecular electron transfer is involved. Less straightforward kinetics may arise with redox reactions that involve metal complex or radical intermediates, or multi-electron transfer, as in the reduction of Cr(VI) to Cr(III). Reactants with different equivalences as in the noncomplementary reaction... 

Nitration of triazole and its C-monoalkyl derivatives fails. Aryltriazoles are nitrated on the benzene ring but 3-p-nitrophenyltriazole (112) in which the benzene ring is deactivated affords the N-nitro derivative (113). This rearranges to the C-nitro compound (Scheme 36) through an isotriazole intermediate on kinetic evidence for a first order intramolecular rearrangement (72CC37). 

All of the relevant bis-chelate complexes, [Ni(biL)2], undergo the interconversion faster than the [NiX2L2] examples discussed earlier. As a consequence, the low-temperature limit has not been reached in NMR studies of these compounds, and rate data (other than minimum limits) are lacking. Nevertheless, the concensus is that these, too, isomerize by a first-order intramolecular twist. 

The reaction of [OH] with [Co(NH3)jNC5H5] yields an OH adduct to the aromatic ring (A = 325 nm = 1.7 X 10 M cm ) , which can undergo disproportionation in competition with first-order intramolecular electron transfer to produce Co (k = 2.3 X 10 s ) and second-order bimolecular reaction to yield Co(III) products with modified ligands a similar competition affects the deprotonated ligand radical (k = 11 s )-, ... 

El Sayed, M. A., Vanishing First and Second order Intramolecular Heavy atom Effects on the (ji —> n) Phosphorescence in Carbonyls, J. Chem. Phys. 1964. 41, 2462 2467 and references therein. 

Exposure to methanol produces a-helix structure, but does not affect the 3-sheet structure. (2) Exposure to ethylene glycol produces helix structure and alters the conventional ordered, intramolecular B-sheet structure to a less ordered, intermolecular B-sheet structure. (3) Varying the pH does not produce a-helix structure, but does alter the B-sheet structure as described in (2). (4) A mechanism for the changes in (2) can... 

Studies of the kinetics and steric course of the first-order intramolecular stereoisomerizations of the Al /3-diketonates tris(2,6-dimethylheptane-3,5-dionato(aluminium(iii) and bis( 1,1,1,5,5,5 -hexafluoropentane-2,4-dionato)alu-minium(m) have been made. It appears that chelates having alkyl or aryl substituents on the /3-diketonate rings isomerize by a rhombic twist mechanism. If fluorocarbon substituents are present, however, a bond-rupture mechanism is more likely, with formation of a square-pyramidal apical five-co-ordinate inter-mediate. ... 

The absolute configuration of ( + )- -(1-naphthylphenylmethylsilyl)-acetophenone, and hence the stereochemistry of its formation, was established when it was found that the compound was thermally isomerized by a first-order, intramolecular reaction to optically pure (- )-a-( 1 -naphthyl-phenylmethylsiloxy)styrene (57). Since this reaction logically could have occurred only with retention of configuration, it follows that (-f)-a-(l-... 

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