Directed Ortho-Metalation of Unprotected Benzoic Acids. Methodology and Regioselective Synthesis of Useful Contiguously 3- and 6-Substituted 2-Methoxybenzoic Acid Building Blocks
作者： Thi-Huu Nguyen , Anne-Sophie Castanet , Jacques Mortier
DOI: 10.1021/OL0530427
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摘要: By treatment with s-BuLi/TMEDA at −78 °C, unprotected 2-methoxybenzoic acid is deprotonated exclusively in the position ortho to carboxylate. A reversal of regioselectivity observed when treated n-BuLi/t-BuOK. These results are general utility for one-pot preparation a variety very simple 3- and 6-substituted acids that not easily accessible by conventional means. The potential usefulness method demonstrated expedient synthesis lunularic acid.
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