The Application of the Schmidt Reaction and Beckmann Rearrangement to the Synthesis of Bicyclic Lactams: Some Mechanistic Considerations

Abstract

The syntheses of some methoxy-substituted bicyclic lactams, of the types 3 and 4, are reported employing two different conditions for the Schmidt reaction of appropriate ketones and employing two different conditions for the Beckmann rearrangement of the corresponding ketoximes. The alkyl to aryl migration ratios of the reactions were determined by high-performance liquid chromatography analysis of the reactions. The mechanisms of the reactions reported are discussed, some limitations of the reported mechanisms identified, and an alternative mechanism proposed in light of the outcomes of the various reactions. Application of the Schmidt reaction and Beckmann rearrangement was used for the synthesis of some chloro bicyclic lactams, of the types 3 and 4.

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