1,3-Dipolar [3+3] Cycloaddition of 1,4-Benzodiazepinone-Based Nitrones with α-Halohydroxamates for Diastereoselective Synthesis of Novel d -Edge Heterocycle-Fused 1,4-Benzodiazepinones.

Promoted by K2 CO3 (2.0 equiv), the 1,3-dipolar [3+3] cy-cloaddition between 1, 4-benzodiazepinone-based nitrones and α-halohydroxamates processed smoothly under the mild reaction conditions and delivered structurally novel and complex cis - or trans -configured d -edge heterocycle-fused 1,4-benzodiazepinones in up to >99% isolated yield with >20:1 dr. The relative configuration of the title chemical entities was clearly identified with the use of single-crystal X-ray structure analysis. The reaction mechanism was assumed to interpret the diastereoselective production of the obtained cis - or trans -configured d -edge heterocycle-fused 1,4-benzodiazepinones. [ABSTRACT FROM AUTHOR]