1,3-Dipolar cycloaddition of unstabilised azomethine ylides by Lewis base catalysis
作者:Shveta Pandiancherri、Sarah J. Ryan、David W. Lupton
DOI:10.1039/c2ob26047f
日期:——
Lewis base catalysed 1,3-dipolar cycloaddition between α,β-unsaturated acyl fluorides and N-[(trimethylsilyl)methyl]amino ethers has been achieved using 1 mol% DMAP. Competition experiments and 19F-NMR studies indicate that the cycloaddition occurs preferentially between the α,β-unsaturated acyl fluoride and the unstabilised azomethine ylide. In addition, an enantioselective variant, using chiral isothiourea
使用1 mol%的酸,可实现Lewis碱催化的α,β-不饱和酰基氟与N -[(三甲基甲硅烷基)甲基]氨基醚之间的1,3-偶极环加成反应地图。竞争实验和19 F-NMR研究表明,环加成反应优先发生在α,β-不饱和酰基氟与不稳定的甲亚胺基立德之间。另外,使用手性异硫脲催化剂的对映体选择性变体的ee为14%。