Lithiation of 2-chloro- and 2-methoxypyridine with lithium dialkylamides: Initial ortho-direction or subsequent lithium ortho-stabilization?

被引：30

作者：

Gros, P ^{[1
]}

Choppin, S ^{[1
]}

Fort, Y ^{[1
]}

机构：

[1] Univ Nancy 1, Fac Sci, CNRS, UHP,UMR 7565, F-54506 Vandoeuvre Les Nancy, France

来源：

JOURNAL OF ORGANIC CHEMISTRY | 2003年 / 68卷 / 06期

关键词：

D O I：

10.1021/jo026559u

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The lithiation pathway of 2-chloro and 2-methoxypyridine with LDA and LTMP has been investigated using deuterated probes. The availability of both H-6 and H-3 protons on the pyridine nucleus was found to be critical to ensure complete C-3 lithiation. We thus concluded that the C-3 lithiation was not a straightforward process. A mechanism involving precomplexation of lithium dialkylamides near the H-6 proton and formation of a 3,6-dilithio pyridine intermediate is proposed.

引用

页码：2243 / 2247

页数：5

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