Photochemical reaction mechanisms of 2-nitrobenzyl compounds:: 2-Nitrobenzyl alcohols form 2-nitroso hydrates by dual proton transfer

被引：81

作者：

Gaplovsky, M ^{[1
]}

Il'ichev, YV ^{[1
]}

Kamdzhilov, Y ^{[1
]}

Kombarova, SV ^{[1
]}

Mac, M ^{[1
]}

Schwörer, MA ^{[1
]}

Wirz, J ^{[1
]}

机构：

[1] Univ Basel, Dept Chem, CH-4056 Basel, Switzerland

来源：

PHOTOCHEMICAL & PHOTOBIOLOGICAL SCIENCES | 2005年 / 4卷 / 01期

关键词：

D O I：

10.1039/b409927c

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Irradiation of 2-nitrobenzyl alcohol (1, R = H) and 1-(2-nitrophenyl) ethanol (1, R = Me) in various solvents yields 2-nitroso benzaldehyde (4, R = H) and 2-nitroso acetophenone (4, R = Me), respectively, with quantum yields of about 60%. The mechanism of this reaction, known since 1918, was investigated using laser ash photolysis, time-resolved infrared spectroscopy (TRIR), and O-18-labeling experiments. The primary aci-nitro photoproducts 2 react by two competing paths. The balance between the two depends on the reaction medium. Reaction via hydrated nitroso compounds 3 formed by proton transfer prevails in aprotic solvents and in aqueous acid and base. In water, pH 3 8, the classical mechanism of cyclization to benzisoxazolidine intermediates 5, followed by ring opening to carbonyl hydrates 6, predominates. The transient intermediates 3 and 6 were identified by TRIR. Potential energy surfaces for these reactions were mapped by density functional calculations.

引用

页码：33 / 42

页数：10

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[1] BIOLOGICALLY USEFUL CHELATORS THAT RELEASE CA-2+ UPON ILLUMINATION [J].