Naslov
Substituent effects in the intramolecular photoredox reactions of benzophenones in aqueos solutions

Autori
Basarić, Nikola ; Mitchell, Devin ; Wan, Peter

Izvornik
Canadian Journal of Chemistry (0008-4042) 85 (2007), 9; 561-571

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
intramolecular photoredox; acid catalysis; meta effect; benzophenone photochemistry

Sažetak
A number of α-hydroxy-3-benzylbenzophenones 7-11 have been synthesized for the purpose of studying the effect of a phenyl substituent on the intramolecular photoredox reaction of 3-(hydroxymethyl)benzophenone (5) discovered in our laboratory. This latter compound was found to undergo a unimolecular (formal) intramolecular redox reaction upon photolysis in aqueous acid that results in clean reduction of the benzophenone ketone (to secondary alcohol) and oxidation of the alcohol to aldehyde. Three of the phenyl-substituted compounds with simple phenyl (7), p-methylphenyl (8) and p-methoxyphenyl (9) were found to undergo the acid-catalyzed intramolecular photoredox reaction with the observation that 9 also undergoes a residual photoredox reaction that is not acid-mediated and may involve initial photoinduced electron transfer which is supported by LFP data. The m-methoxyphenyl (10) compound did not undergo the reaction. The trend in observed relative reactivity may be partially rationalized by examining changes in molecular orbital coefficients observed in the calculated HOMO’s and LUMO’s. The photoredox reaction has also been applied twice in succession in a single compound 11 demonstrating that may be useful for sequential photoredox reactions in a multi-functional compound.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA