Bicyclo heptane-7 -carboxylic acid synthesis

A Wagner-Meerwein rearrangement via a bridged carbenium ion has been observed in the electrodecarboxylation of bicyclo[2.2.1]heptane-2-carboxylic acids (CXVIIa, CXVIIb, and CXVIIc), leading to the formation of the same products (CXVIII and CXIX) [Eq. (58)] [174]. This method has been successfully applied to synthesis of useful intermediates for natural product synthesis. Some examples are given in Eqs. (59) and (60) [175-179]. 

Monoester 4-(methoxycarbonyl)bicyclo[2.2.1]heptane-l-carboxylic acid 59 (Figure 4.17) is a building block of many potential therapeutic candidates for inhibitors of 11-p-hydroxysteroid dehydrogenase type 1 enzyme and their use in the treatment of non-insulin-dependent type 2 diabetes, insulin resistance, obesity, lipid disorders, metabolic syndrome, and CNS disorders. It is also required for the synthesis of 5-hydroxytryptamine receptor agonists, useful for the treatment of anxiety disorders and schizophrenia [90,91]. 

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