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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]

In the presence of Na2 CO3 , conjugate addition of α-halo hydrazones to nitroso compounds proceeded readily to give polyfunctionalized nitrones in reasonable chemical yields and excellent stereoselectivities. The chemical structure and the stereochemical configuration of the products were unambiguously identified by an X-ray single-crystal structural analysis. [ABSTRACT FROM AUTHOR]

Under the catalysis of PhCO2 H, the 1,3-dipolar [3+2] cyclo-addition between pyrazolone-based olefins and N , N ′-cyclic azomethine imines proceeded readily, thus delivering structurally novel spiropyrazolones with up to 98% yield and >20:1 dr. The relative stereochemical configuration of the obtained spiropyrazolones was unambiguously -assigned by X-ray single-crystal structure analysis. The diastereoselective formation of the title spiropyrazolones was interpreted by the hypothesized reaction mechanism. [ABSTRACT FROM AUTHOR]

In the presence of Pd2 (dba)3 ·CHCl3 (2.5 mol%), PPh3 (10 mol%), and 60% NaH (1.5 equiv), the formal [5+3] cycloaddition between isatin-based α-(trifluoromethyl)imines and vinyloxiranes proceeded readily in 1,2-DCE at 40 ℃ and afforded cis -configured medium-heterocycle-fused spirooxindoles in the reasonable chemical yields with >20:1 dr. The relative stereochemical configuration of the title products was identified by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]