Free-radical reactions of 3,3-dimethylbutene, 3-methyl-3-phenylbutene, and tert-pentylbenzene induced by di-tert-butyl peroxide

Ultraviolet irradiation of hydrocarbon solutions of 2,4,6-tri-tert-butylnitrosobenzene (1) formed [Formula: see text] The initial products were 2-methyl-1-nitroso-2-(3,5-di-tert-butyl)-phenylpropane (Ar—C(CH3)2CH2NO)2 (3) and a mixed dimer (4). Secondary and minor photoproducts isolated included 2-methyl-2-(3,5-di-tert-butyl)phenylpropanal oxime (5), 2-methyl-2-(3,5-di-tert-butyl)phenylpropanal (6) derived from 5, and 1,3,5-tri-tert-butylbenzene (7). The initial products are explained by formation of a tri-tert-butylphenyl radical (15), rearrangement of a hydrogen atom from an orthotert-butyl to the ring in 15, and rapid recombination of the neophyl radical with nitric oxide. Photolysis of 2,5-di-tert-butylnitrosobenzene (2) initially gave [Formula: see text] (10). Product analysis indicated a comparatively complex mixture including 1,4-di-tert-butylbenzene (11), 2,5-di-tert-butylphenol (12), and 2,5-di-tert-butylanilino-p-(2,5-di-tert-butyl)quinone (13). Evidence indicates that 12 and 13 form from free radical reactions involving 10 and the 2,5-di-tert-butylphenyl radical. The different photochemistry of 1 and 2 is discussed in terms of differential steric and conformational effects on the nitroso function which also is evident in their ultraviolet spectra.

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ChemInform Abstract: Low Temperature Free-Radical Reactions Initiated with tert-Butyl p-Benzoylperbenzoate.

Chemischer Informationsdienst ◽

10.1002/chin.198615122 ◽

1986 ◽

Vol 17 (15) ◽

Author(s):

P. GOTTSCHALK ◽

D. C. NECKERS

Keyword(s):

Free Radical ◽

Low Temperature ◽

Radical Reactions ◽

Free Radical Reactions ◽

Tert Butyl

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Regio-and chemo-selectivity of adamantane halogenation by Gif-Barton and metalloporphyrin catalysis and by classical free-radical reactions

Tetrahedron Letters ◽

10.1016/s0040-4039(00)78416-4 ◽

1994 ◽

Vol 35 (41) ◽

pp. 8033-8036

Author(s):

F Minisci

Keyword(s):

Free Radical ◽

Radical Reactions ◽

Free Radical Reactions

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The initial reaction mechanism and thermal sensitivity of a fluoropolymer-containing energetic molecular system: the coupling effect of interfacial interactions and free radical reactions

CrystEngComm ◽

10.1039/d0ce01681k ◽

2021 ◽

Vol 23 (16) ◽

pp. 3006-3014

Author(s):

Wen Qian

Keyword(s):

Free Radical ◽

Coupling Effect ◽

Molecular System ◽

Thermal Sensitivity ◽

Radical Reactions ◽

Initial Reaction ◽

Interfacial Interactions ◽

Free Radical Reactions ◽

Molecular Systems ◽

Reactive Molecular Dynamics

A strategy combining classic and reactive molecular dynamics is applied to find the coupling effect of interfacial interactions and free radical reactions during the initial thermal decomposition of fluoropolymer-containing molecular systems.

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Further studies on free-radical pathology in the major central nervous system disorders: effect of very high doses of methylprednisolone on the functional outcome, morphology, and chemistry of experimental spinal cord impact injury

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y82-210 ◽

1982 ◽

Vol 60 (11) ◽

pp. 1415-1424 ◽

Cited By ~ 150

Author(s):

H. B. Demopoulos ◽

E. S. Flamm ◽

M. L. Seligman ◽

D. D. Pietronigro ◽

J. Tomasula ◽

...

Keyword(s):

Spinal Cord ◽

Central Nervous System ◽

Nervous System ◽

Free Radical ◽

Tissue Injury ◽

Functional Restoration ◽

Radical Reactions ◽

Free Radical Reactions ◽

Cord Injury

The hypothesis that pathologic free-radical reactions are initiated and catalyzed in the major central nervous system (CNS) disorders has been further supported by the current acute spinal cord injury work that has demonstrated the appearance of specific, cholesterol free-radical oxidation products. The significance of these products is suggested by the fact that: (i) they increase with time after injury; (ii) their production is curtailed with a steroidal antioxidant; (iii) high antioxidant doses of the steroidal antioxidant which curtail the development of free-radical product prevent tissue degeneration and permit functional restoration. The role of pathologic free-radical reactions is also inferred from the loss of ascorbic acid, a principal CNS antioxidant, and of extractable cholesterol. These losses are also prevented by the steroidal antioxidant. This model system is among others in the CNS which offer distinctive opportunities to study, in vivo, the onset and progression of membrane damaging free-radical reactions within well-defined parameters of time, extent of tissue injury, correlation with changes in membrane enzymes, and correlation with readily measurable in vivo functions.

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