SET activation of nitroarenes by 2-azaallyl anions as a straightforward access to 2,5-dihydro-1,2,4-oxadiazoles

• DOI: 10.1038/s41467-021-26767-x
• Publication Date: 2021-12-03T11:03:12Z
• Authors: Dong Zou; Lishe Gan; Fan Yang; Huan Wang; Youge Pu; Jie Li; Patrick J. Walsh
• Keywords: Scope (computer science); Closure (psychology)

Abstract The use of nitroarenes as amino sources in synthesis is challenging. Herein reported an unusual, straightforward, and transition metal-free method for the net [3 + 2]-cycloaddition reaction 2-azaallyl anions with nitroarenes. products this are diverse 2,5-dihydro-1,2,4-oxadiazoles (>40 examples, up to 95% yield). This does not require external reductant reduce nitroarenes, nor it employ nitrosoarenes, which often used N–O cycloadditions. Instead, proposed that anions, behave super electron donors (SEDs), deliver nitroarene generate a radical anion. A downstream coupling newly formed nitrosoarene followed by ring closure afford observed products. pathway supported computational studies experimental evidence. Overall, uses readily available materials, green, exhibits broad scope.