The Regiospecific C-Benzylation of Heterocyclic Ketene Aminals with Ethyl 2-(Bromomethyl)benzoate: A Simple Route to 1H-Imidazo[1,2-b][2]benzazepin-5-one Derivatives

Abstract

Heterocyclic ketene aminals reacted with ethyl 2-(bromomethyl)benzoate in refluxing acetonitrile to afford the C-benzylated products that underwent intramolecular cyclocondensation reaction to produce ε-lactam fused heterocyclic compounds. The heterocyclic ring size effect on the reaction was discussed.

Key words

heterocyclic ketene aminals - ethyl 2-(bromomethyl)benzoate - 1H-imidazo[1,2-b][2]benzazepin-5-one

References

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9

All compounds gave satisfactory elemental analyses C, ±0.33; H, ±0.30; N, ±0.38.