Regioselectivity in arene-catalyzed reductive lithiation of acetals of chlorobenzaldehydes

被引：9

作者：

Azzena, U

Dettori, G

Sforazzini, G

Yus, M

Foubelo, F

机构：

[1] Univ Sassari, Dipartimento Chim, I-07100 Sassari, Italy

[2] Univ Alicante, Fac Ciencias, Dept Quim Organ, E-03080 Alicante, Spain

来源：

TETRAHEDRON | 2006年 / 62卷 / 07期

关键词：

metalation; organometals; reduction; regioselectivity;

D O I：

10.1016/j.tet.2005.11.006

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The regioselectivity of arene-catalyzed reductive lithiation of acetals of chlorobenzaldehydes strongly depends on the form of lithium metal employed as a reducing agent. According to previous findings, naphthalene catalyzed reductions run in the presence of lithium powder (high Na content) led to competitive metalations of both aromatic carbon-chlorine and benzylic carbon-oxygen bonds. At variance with these results, naphthalene catalyzed reductions run in the presence of lithium wire (either high or low Na content) led to highly regioselective metalation of aromatic carbon-chlorine bonds. These results disclose new possibilities of selective applications of arene-catalyzed reductive lithiation reactions. (c) 2005 Elsevier Ltd. All rights reserved.

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收藏

页码：1557 / 1563

页数：7

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