A flash photolysis and theoretical study of the reaction of arylnitroso oxides with phosphorus(III) compounds

Khursan, V. S.; Ковалева, О. А.; Chainikova, E. M.; Talipov, Marat R.; Safiullin, R. L.

doi:10.1134/s0018143910040053

Cited by 4 publications

(4 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It has been shown using a number of model systems that cycloaddition is a typical reaction of nitroso oxides with alkenes, though the reaction with tetracyanoethylene occurs via the epoxidation mechanism. 14,23 Yet another example of the cis/trans chemoselectivity of aryl nitroso oxides is that only trans-ArNOO reacts with trivalent phosphorus compounds: the kinetics parameters of the reactions studied 18,24 are in favor of the mechanism of (3 + 1) cycloaddition of the nitroso oxide moiety to the phosphorus atom, and the results of theoretical calculations 25 confirm this mechanism.…”

Section: ■ Introductionmentioning

confidence: 95%

Conformational Transformations in Aromatic Nitroso Oxides

2016

View full text Add to dashboard Cite

A systematic theoretical study on conformational transformations of monosubstituted (ortho- and para-) aromatic nitroso oxides R-C6H4NOO was performed. The existence of two rotation axes enables two types of conformational transitions in substituted arylnitroso oxides: trans/cis (rotation around the N-O bond) and syn/anti (rotation around the C-N bond, which is important in ortho isomers). The complete set of conformers was localized for R-C6H4NOO using four selected density functional (M06-L, mPWPW91, OLYP, and HCTH) and augmented polarization basis set of triple splitting. It was found that the activation enthalpy of the trans-cis conformational transition is nearly insensitive to the nature of R and ranges within 58-60 kJ/mol for para isomers. The ortho substituent has an insignificant effect on ΔH(≠)trans→cis: it increases this value by ∼5 kJ/mol in syn isomers and decreases it by ∼3 kJ/mol in anti isomers. On the contrary, the syn-anti conformational barrier is considerably affected by the substituent R; an increase in the electron-withdrawing properties of R decreases ΔH(≠)syn→anti. The activation enthalpies grow with increasing polarity of the solvent, as it was found using IEFPCM calculation. The values of relaxation time for all conformational equilibria were calculated and compared with known lifetimes of aromatic nitroso oxides. Our results suggest that syn/anti transitions occur fast enough in the scale of the experimental lifetime. However, trans/cis transformations proceed more slowly. And under certain conditions discussed in the paper, the rate of this conformational transition limits that of irreversible decay of nitroso oxide.

show abstract

Section: ■ Introductionmentioning

confidence: 95%

Conformational Transformations in Aromatic Nitroso Oxides

2016

View full text Add to dashboard Cite

show abstract

“…The reaction parameter ρ value of Hammett's dependence versus constants σ of substituents in the aromatic ring of nitroso oxides equals 1.5 (r = 0.94) in the case of Ph 3 P 130 and 1.2 (r = 0.93) in the case of (Ph 3 O) 3 P 131 . If the substituent is varied in the aromatic ring of phosphine, then the ρ value equals −1.5 (r = 0.995) in the case of 4-methoxyphenylnitroso oxide and −1.2 (r = 0.995) in the case of 4-methylphenylnitroso oxide 132 . The activation parameters of the reaction of nitroso oxides with triphenylphosphite in acetonitrile were determined (Table 22) 131 .…”

Section: Oxygen Atom Transfer Reactionsmentioning

confidence: 99%

“…This value nearly coincides with the reaction rate constant of the trans-form of this nitroso oxide with Ph 3 P in acetonitrile in the absence of 93 [5.5 × 10 5 L mol −1 s −1 (Table 21) 130 ]. The theoretical investigations have shown that there are two possible pathways for proceeding of the reaction of nitroso oxides with R 3 P (Scheme 21) 132 . In pathway (a), nitroso oxide behaves as a diradical and transfers the terminal oxygen atom of the NOO group to the phosphorus atom in one elementary step.…”

Section: Oxygen Atom Transfer Reactionsmentioning

confidence: 99%

See 1 more Smart Citation

The chemistry of nitroso oxides

Chainikova

Khursan

Safiullin

2014

Patai's Chemistry of Functional Groups

View full text Add to dashboard Cite

Nitroso oxides (RNOO) are the isoelectronic analogs of carbonyl oxides (R 2 COO) and ozone (O 3 ) and, as well as these species, possess a three‐centered 4π‐electron system, which determines their chemical properties and reactivity unusual for a family of peroxides. The review is focused on the chemistry of the parent nitroso oxide (HNOO) and its aromatic analogs (ArNOO). The structure, spectral properties, methods for generation, reactivity and mechanisms of various transformations of these species both in the gas and condensed media are discussed in detail. An aromatic substituent significantly stabilizes the π‐system of nitroso oxide. The typical reactions of nitroso oxides are O‐transfer to an appropriate substrate or [3+2]‐cycloaddition to unsaturated bonds. Special attention was paid to the redox isomerization of arylnitroso oxides with ring cleavage that leads to the formation of diene nitrile oxides.

show abstract