Synthesis of 2,3,4,5-Tetrahydro-1,5-methano-1H-3-benzazepine via Oxidative Cleavage and Reductive Amination Strategies

Abstract

Preparations of 2,3,4,5-tetrahydro-1,5-methano-1H-3-benzazepine (5) from benzonorbornadiene (1) by oxidative cleavage and reductive amination sequences were investigated. Osmium-mediated dihydroxylation of 1 followed by NaIO₄ cleavage, reductive amination and debenzylation provides 5 in 64-73% yield overall in three operations. A tandem ozonolysis-reductive amination procedure gives 5 as the tosylate salt from benzonorbornadiene with no isolation of intermediates in 28% yield.

oxidation - ozonolysis - amination - reduction - bicyclic compounds

References

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