Easy photochemical preparation of 2-dimethylaminophenylfurans, -pyrroles and -thiophenes

被引：36

作者：

Guizzardi, B ^{[1
]}

Mella, M ^{[1
]}

Fagnoni, M ^{[1
]}

Albini, A ^{[1
]}

机构：

[1] Univ Pavia, Dept Organ Chem, I-27100 Pavia, Italy

来源：

TETRAHEDRON | 2000年 / 56卷 / 47期

关键词：

photochemistry; arylations; furans; thiophenes; pyrroles;

D O I：

10.1016/S0040-4020(00)00909-1

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

2-(4-N,N-dimethylaminophenyl) heterocycles are smoothly obtained from the photolysis of 4-chloro-N,N-dimethylaniline in acetonitrile in the presence of furan, pyrrole, thiophene and some of their methyl derivatives bearing a free or-position. With 2,5-dimethyl heterocycles the arylation occurs with equal efficiency in the beta position. In the case of furan, when the irradiation is carried out in methanol, cis/trans 2-aryl-5-methoxy-2,5-dihydro adducts are obtained. The reaction is rationalized as involving heterolytic cleavage of the C-Cl bond in the triplet state of the aniline. The intermediacy of the thus formed triplet aryl cation explains the observed high regio- and chemoselectivity of the process. (C) 2000 Elsevier Science Ltd. All rights reserved.

引用

页码：9383 / 9389

页数：7

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[2]

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