A combination of polarity reversal, Diels-Alder cycloaddition and skeletal remodeling to access pyridine-fused
Huabin Han1, Chaoyang Li1, Xinyue Niu1
1College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004, China. wangqilin@henu.edu.cn.
Abstract:
An unprecedented cascade strategy consisting of polarity reversal, normal electron-demand Diels-Alder cycloaddition and skeletal remodeling was developed to construct novel pyridine-fused nitrones in up to 82% yield. The key to the success was the umpolung process, which transformed the electron-deficient 3-nitropyridinium ring into a reactive, π-extended cyclic nitroalkene, serving as a rarely reported hetero-diene to participate in normal Diels-Alder cycloadditions.
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