Formamidines, hydride reduction

Formamidines such as 81 may be lithiated with s-BuLi or r-BuLi and give stabilised organolithiums 82 which react with a wide range of electrophiles. Cleavage is much easier than cleavages in the amide series acidic methanolysis gives a secondary amine 83 while hydride reduction gives a tertiary amine 84.57... 

Propyl-1-azacycloheptane has been prepared by reduction of 2-aza-l-oxo-3-propylcycloheptane with lithium aluminum hydride, and from azacycloheptane by conversion to its formamidine, alkylation with 1-iodopropane, and subsequent hydrazinolysis... 

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