Knoevnagel condensation

Formal oxidation of pyrrolidine to the succinimide stage affords a series of compounds used as anticonvulsant agents for treatment of seizures in petit mal epilepsy. Knoevnagel condensation of benzaldehyde with ethyl cyanoacetate affords the unsaturated ester, 9. Conjugate addition of cyanide ion leads to the di-nitrile ester (10). Hydrolysis in mineral acid affords the succinic acid (11), presumably by decarboxylation of the intermediate tricarboxyllie acid. Lactamization with methylamine gives phensuximide (12). ... 

Use of acetophenone rather than benzaldehyde in the Knoevnagel condensation reaction affords the unsaturated ester, 13. Elaboration of this to the succinimide by a scheme analogous to that above leads to the anticonvulsant agent methsuximide (14)... 

Benzaldehyde and malonitrile undergoes Knoevnagel Condensation to give an unsaturated cyanoester whieh on reaetion with phenyl magnesium bromide yields an intermediate. This on hydrolysis and subsequent deearboxylation yields a nitrile which on reduction gives an amine. The resulting amine on alkylation with 2-chloro-l-phenylpropane yields the prenylamine base which on treatment with lactic acid affords the official product. 

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