Acid-Catalyzed 1,3-Dipolar Cycloaddition of 2<i>H</i>-Azirines with Nitrones: An Unexpected Access to 1,2,4,5-Tetrasubstituted Imidazoles
作者:Anikó Angyal、András Demjén、János Wölfling、László G. Puskás、Iván Kanizsai
DOI:10.1021/acs.joc.9b03288
日期:2020.3.6
The first 1,3-dipolar cycloaddition of 2H-azirines with nitrones, a straightforward approach toward the regioselective synthesis of 1,2,4,5-tetrasubstituted imidazoles, is reported. This trifluoroacetic acid-catalyzed protocol tolerates a broad range of aliphatic and aromatic substrates, offering an efficient access to highly diverse, multisubstituted imidazoles in isolated yields up to 83% under mild
据报道,2H-叠氮基与硝酮的第一个1,3-偶极环加成反应是对1,2,4,5-四取代的咪唑进行区域选择性合成的直接方法。该三氟乙酸催化的方案可耐受多种脂族和芳族底物,在温和条件下,分离出的收率高达83%,可高效获得高度多样化的多取代咪唑。