A mild and efficient method for the regioselective iodination of pyrazoles

被引：66

作者：

Rodríguez-Franco, MI ^{[1
]}

Dorronsoro, I ^{[1
]}

Hernández-Higueras, AI ^{[1
]}

Antequera, G ^{[1
]}

机构：

[1] CSIC, Inst Quim Med, E-28006 Madrid, Spain

来源：

TETRAHEDRON LETTERS | 2001年 / 42卷 / 05期

关键词：

pyrazole; iodination; ceric ammonium nitrate; regioselectivity;

D O I：

10.1016/S0040-4039(00)02136-5

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The iodination of N-H or N-benzylpyrazoles using elemental iodine in the presence of CAN as the in situ oxidant is a mild and efficient method to prepare 4-iodopyrazoles containing even electron-withdrawing substituents. The reaction is regioselective since the iodine atom preferred pyrazole instead of the benzyl group, and the 4-pyrazolic position instead of other possible positions in the heterocycle. (C) 2001 Elsevier Science Ltd. All rights reserved.

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页码：863 / 865

页数：3

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