合成路线1

The same product can be obtained from reaction of cyclohexenone (I) with ethyl cyanoacetate (A) in the presence of ammonia affords the Guareschi salt (II), which is hydrolyzed and decarboxylated to give 1,1-cyclohexanediacetic acid (III). The anhydride (IV) can be treated with the N-hydroxyimide (VII) via a Lossen type rearrangement by conversion of (VII) to N-benzenesulfonyloxylmide (VIII) and subsequent reaction with triethylamine in methanol followed by hydrolysis of the urethanester (IX). The free amino acid is finally obtained from the hydrochloride (X) via anion exchange.