| Abstract
| - The reaction of various bromobenzoic acids 1 witharylacetonitriles 3 in the presence of LDA at−70 °C gave predominantly 2-cyanobenzoic acids 4 plusminor amounts of 3-(arylcyanomethyl)benzoic acids 5 and debrominated benzoic acids 6.The reaction is thought to proceed through abenzyne-3-carboxylate intermediate 2, which is formed at−70 °C upon the addition of thearylacetonitrile 3 to a solution of the appropriate lithiumhalobenzoate and excess LDA. The base-initiated generation of an aryne intermediate from a haloarene at suchlow temperatures isunprecedented. To confirm the orientation of the cyano andcarboxylic acid groups, 4-methoxy-2-cyanobenzoic acid (4f) was converted to the correspondinganhydride (8) via phthalic acid (7)andto 3,3-dimethyl- and3,3-di-n-butyl-2,3-dihydro-5-methoxy-4-(4-methoxyphenyl)-methyl-1H-isoindol-1-ones (9).
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