Synthesis of the benzazepin-4-one ring system via dipolar cycloaddition of N-phenylnitrones with activated allenes

A Padwa, DN Kline, BH Norman

Index: Padwa, Albert; Kline, Donald N.; Norman, Bryan H. Journal of Organic Chemistry, 1989 , vol. 54, # 4 p. 810 - 817

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Citation Number: 44

Abstract

The 1, 3-dipolar cycloaddition of N-phenyl-C-phenylnitrone with several allenes containing electron-withdrawing groups has been investigated. The cycloaddition proceeds in good yield to give a substituted benzazepin-4-one. The structure of the cycloadduct was established by high-field NMR spectroscopy as well as by an X-ray crystal structure. The results are consistent with a mechanism that involves dipolar cycloaddition of the nitrone ...