Intramolecular radical cyclisations to pyridines

被引：30

作者：

Harrowven, DC ^{[1
]}

Sutton, BJ

Coulton, S

机构：

[1] Univ Southampton, Dept Chem, Southampton SO17 1BJ, Hants, England

[2] GlaxoSmithKline, Harlow CM19 5AW, Essex, England

来源：

TETRAHEDRON LETTERS | 2001年 / 42卷 / 51期

关键词：

radicals and radical reactions; pyridines; nitrogen heterocycles; cascade reactions;

D O I：

10.1016/S0040-4039(01)01937-2

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Intramolecular radical additions to the alpha-, beta- and gamma -carbons of a pyridine have each been shown to be facile processes. When a cis-alkene conjoins an ortho-iodoarene and a pyridine. radical cyclisation induced by homolysis of the carbon to iodine bond favours a 6-exo, endo-trig course. With a two carbon alkane conjoining the ortho-iodoarene and the pyridine, intermolecular hydrogen atom abstraction. 6-exo/endo-trig cyclisation and 5-exo-trig cyclisation modes compete. That the spirocyclic intermediates formed in the 5-exo-trig cyclisation rearrange with migration of the alkyl chain is noteworthy. (C) 2001 Elsevier Science Ltd. All rights reserved.

引用

页码：9061 / 9064

页数：4

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