Hexahydrosalicylic acid

Salicylic acid, upon reaction with amyl alcohol and sodium, reduces to a ring-opened aliphatic dicarboxylic acid, ie, pimelic acid (eq. 5). The reaction proceeds through the intermediate cyclohexanone-2-carboxylic acid. This novel reaction involves the fission of the aromatic ring to tfj-hexahydrosalicylic acid when salicylic acid is heated to 310°C in an autoclave with strong alkali. Pimelic acid is formed in 35—38% yield and is isolated as the diethyl ester. 

The azide of salicylic acid does not provide the hydroxyindoxazene (indoxazen-3-one) on heating in benzene instead, it gives the benzo-xazolin-2-one (26) via a Curtius rearrangement.47 A similar reaction has been reported with a hexahydrosalicylic acid azide.53... 

Besthom, Ber., 1896, 29, 2662. Hexahydrosalicylic Acid (CyclohexanoJr2-carboxylic acid, 2-hyaroxyhexahydrobemoic acid)... 

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