The reaction of various bromobenzoic acids 1 with arylacetonitriles 3 in the presence of LDA at -70 degrees C gave predominantly 2-cyanobenzoic acids 4 plus minor amounts of 3-(arylcyanomethyl)benzoic acids 5 and debrominated benzoic acids 6. The reaction is thought to proceed through a benzyne-3-carboxylate intermediate 2, which is formed at -70 degrees C upon the addition of the arylacetonitrile 3 to a solution of the appropriate lithium halobenzoate and excess LDA. The base-initiated generation of an aryne intermediate from a haloarene at such low temperatures is unprecedented. To confirm the orientation of the cyano and carboxylic acid groups, 4-methoxy-2-cyanobenzoic acid (4f) was converted to the corresponding anhydride (8) via phthalic acid (7) and to 3,3-dimethyl- and 3,3-di-n-butyl-2,3-dihydro-5-methoxy-4-(4-methoxyphenyl)-methyl-1H-isoindol-1-ones (9).

中文翻译：

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由溴代苯甲酸与芳基乙腈和LDA的反应制备2-氰基苯甲酸。

在LDA的存在下，各种溴代苯甲酸1与芳基乙腈3在-70℃下反应，主要生成2-氰基苯甲酸4加少量的3-（芳基氰甲基）苯甲酸5和脱溴的苯甲酸6。继续进行苯甲酸3-羧酸酯中间体2，其在将芳基乙腈3添加到适当的卤代苯甲酸锂和过量的LDA的溶液中时在-70℃形成。在如此低的温度下由卤代芳烃碱引发的芳烃中间体的生成是前所未有的。为了证实氰基和羧酸基团的取向，将4-甲氧基-2-氰基苯甲酸（4f）通过邻苯二甲酸（7）转化为相应的酸酐（8），并转化为3,3-二甲基-和3,3。 -二正丁基-2，