Intermolecular [5 + 1]-Cycloaddition between Vinyl Diazo Compounds and <i>tert</i>-Butyl Nitrite to 1,2,3-Triazine 1-Oxides and Their Further Transformation to Isoxazoles
作者:Luca De Angelis、Haifeng Zheng、Matthew T. Perz、Hadi Arman、Michael P. Doyle
DOI:10.1021/acs.orglett.1c02352
日期:2021.8.20
1,2,3-Triazine 1-oxides are formed by nitrosyl addition from tert-butyl nitrite to the vinylogous position of vinyl diazo compounds. This transformation, which is a formal intermolecular [5 + 1] cycloaddition, occurs under mild conditions, with high functional group tolerance and regioselectivity, and can be employed for late-stage functionalization. Upon heating at refluxing chlorobenzene temperature
1,2,3-三嗪 1-氧化物是通过亚硝酸叔丁酯与乙烯基重氮化合物的邻位位置的亚硝酰基加成而形成的。这种转化是正式的分子间 [5 + 1] 环加成,在温和的条件下发生,具有高官能团耐受性和区域选择性,可用于后期功能化。在回流的氯苯温度下加热时,这些三嗪-N-氧化物经历二氮挤压以非常高的产率形成异恶唑。