Methylbenzene cation radical [alpha]-fragmentation selectivities revealed in SET-photoadditions of p-xylene derivatives to 1,4-dicyanonaphthalene

Journal Article · Fri Feb 12 04:00:00 EST 1993 · Journal of Organic Chemistry; (United States)

DOI:https://doi.org/10.1021/jo00056a029· OSTI ID:6304451

d'Alessandro, N; Albini, A ^[1]

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1. Univ. of Pavia (Italy) Univ. of Torino (Italy)

SET-promoted photoreactions of selected p-xylene derivatives, including p-xylene, p-phenylenediacetic acid, p-bis[(trimethylsilyl)methyl]benzene, p-[(trimethylsilyl)methyl]toluene, p-tolylacetic acid, and p[(trimethylsilyl)methyl]phenylacetic acid, to 1,4-dicyanonaphthalene have been investigated. These processes lead to clean and selective formation of 1:1 adducts whose nature is controlled by [alpha]-heterolytic fragmentation reactions occurring at benzylic positions of arene cation radicals which serve as key reactive intermediates. The results indicate that the relative rates of cation radical fragmentations of the type ([ArCH[sub 2]E][sup [sm bullet]+] + B: [yields] ArCH[sub 2][sup [sm bullet]] + BE) depend on the nature of the electrofugal group, E, in the following order: E = SiMe[sub 3] > CO[sub 2]H > H. The experimental basis for these conclusions is discussed. 23 refs., 1 tab.

• OSTI ID: 6304451
• Journal Information: Journal of Organic Chemistry; (United States), Journal Name: Journal of Organic Chemistry; (United States) Vol. 58:4; ISSN 0022-3263; ISSN JOCEAH
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400500* -- Photochemistry
ADDUCTS
ALKYLATED AROMATICS
AROMATICS
BENZENE
CARBOXYLIC ACIDS
CATIONS
CHARGED PARTICLES
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
CONDENSED AROMATICS
ELECTRON TRANSFER
FRAGMENTATION
HYDROCARBONS
IONS
KINETICS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PHOTOCHEMICAL REACTIONS
RADICALS
REACTION KINETICS
TOLUENE
XYLENES
YIELDS