An ab initio treatment of the Norrish type-II process in pentane-2-one and the role of tunneling of hydrogen

Rao, V. S. R.; Chandra, Asit K.

doi:10.1016/s0301-0104(96)00293-5

Cited by 7 publications

(1 citation statement)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Proton-transfer processes are of paramount importance in chemistry and biochemistry, and consequently they have been extensively studied . While a considerable amount of literature was devoted to investigate dynamical effects − as well as hydrogen tunneling, , many other focused on the static aspects of the problem, − i.e., on the characterization of the corresponding potential energy surfaces (PES). In this respect, it seems nowadays well established that some proton-transfer processes are characterized by a symmetric single-well potentiall, ,, in which the proton locates midway between the two groups involved.…”

Section: Introductionmentioning

confidence: 99%

Proton Transfer in Dissociative Protonation Processes

1998

View full text Add to dashboard Cite

Proton transfer in dissociative protonation processes involving fluoroadamantane and other smaller model compounds with different reference bases has been studied, through the use of B3LYP density functional theory calculations. All systems investigated are characterized by single-well potential energy curves. Solvent effects on proton-transfer potential energies were studied by means of a self-consistent isodensity polarized continuum model (SCIPCM) approach. It was found that also in solution the proton-transfer potential is single-well. However, the effects of the solvent on the characteristics of the complex are not negligible. The distance between the heavy atoms, and as a consequence the position of the minimum, changes, and the well becomes less deep. For fluoroadamantane the proton transfer leads to the C-F bond fission, so that the equilibrium conformation corresponds to a tightly bound complex between adamantyl cation and hydrogen fluoride, solvated by one molecule of the corresponding reference base.

show abstract

Section: Introductionmentioning

confidence: 99%

Proton Transfer in Dissociative Protonation Processes

1998

View full text Add to dashboard Cite

show abstract

Norrish Type II Reaction

2010

Comprehensive Organic Name Reactions and Reagents

View full text Add to dashboard Cite

The light initiated intramolecular abstraction of a δ‐hydrogen of an excited ketone or aldehyde to generate a 1,4‐biradical, from which different products can form, including alkene, enol, and cyclobutanol and this reaction is generally known as the Norrish type II reaction. This reaction is also called as the Yang reaction. The study finds that this reaction is influenced by both environmental and structural factors. In addition, it is found that both the excited singlet (S1) and triplet (T1) state of a dialkyl ketone can undergo such reaction, whereas an aryl alkyl thioketone proceeds from the excited triplet state (T1), and the reaction of an ester primarily involves the excited triplet (T1). For aliphatic or benzylic hydrogen abstraction, ketones with a lowest π‐π * triplet state are much less reactive than those with the lowest n‐π * triplet state. The mechanism of the reaction for an aryl ketone and special ketones has been discussed. This reaction has been applied in organic synthesis, especially for the generation of free radicals.

show abstract