Bu3SnH-mediated radical cyclisation onto azoles

被引：47

作者：

Allin, Steven M. ^{[1
]}

Barton, William R. S. ^{[1
]}

Bowman, W. Russell ^{[1
]}

Bridge nee Mann, Emma ^{[1
]}

Elsegood, Mark R. J. ^{[1
]}

McInally, Tom ^{[2
]}

McKee, Vickie ^{[1
]}

机构：

[1] Univ Loughborough, Dept Chem, Loughborough LE11 3TU, Leics, England

[2] AstraZeneca R&D Charnwood, Loughborough LE11 5RH, Leics, England

来源：

TETRAHEDRON | 2008年 / 64卷 / 33期

基金：

英国工程与自然科学研究理事会;

关键词：

radical cyclisation; homolytic aromatic substitution; Bu3SnH; imidazole; pyrrole; pyrazole;

D O I：

10.1016/j.tet.2008.06.014

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Alkyl radicals have been cyclised onto pyrroles, imidazoles and pyrazoles, and acyl radicals cyclised onto pyrroles, using Bu3SnH-, (TMS)(3)SiH- and Bu3GeH-mediated aromatic homolytic substitution for the synthesis of bicyclic N-heterocycles. The reactions yield intermediate pi-radicals that lose hydrogen in the rearomatisation step of the aromatic homolytic substitution. Mechanistic studies of these rear-omatisation steps indicate aromatic homolytic substitution in which the initiator or breakdown products from the inhibitor are responsible for the H-abstraction step. (C) 2008 Elsevier Ltd. All rights reserved.

引用

页码：7745 / 7758

页数：14

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