Generation of NH-azomethine imine intermediates through the 1,2-hydrogen shift of hydrazones and their intermolecular cycloaddition reaction with olefinic dipolarophiles
作者:Michihiko Noguchi、Satoshi Matsumoto、Masashi Shirai、Hidetoshi Yamamoto
DOI:10.1016/s0040-4020(03)00593-3
日期:2003.6
The thermal 1,2-hydrogen shift of the hydrazone generates the NH-azomethine imine intermediate in the 4-oxo-4H-pyrido[1,2-a]pyrimidine-3-carbaldehyde system under mild conditions. Therein, the resulting NH-azomethine imine should be stabilized by forming an internal hydrogen bond with the carbonyl oxygen at the 4-position. Its smooth stereoselective intermolecular cycloaddition reaction with olefinic
mild的热1,2-氢转移在温和条件下在4-氧代-4 H-吡啶并[1,2 - a ]嘧啶-3-甲醛体系中生成NH-偶氮甲亚胺亚胺中间体。其中,应通过在4-位与羰基氧形成内部氢键来稳定所得的NH-偶氮甲亚胺。讨论了其与烯烃双极性亲和剂的平滑的立体选择性分子间环加成反应,得到吡唑烷衍生物。