Highly Efficient Darzens Reactions Mediated by Phosphazene Bases under Mild Conditions
作者:Carmine Lops、Paolo Pengo、Lucia Pasquato
DOI:10.1002/open.202200179
日期:2022.10
The first Darzens reaction of α-halo acetate esters with aromatic aldehydes promoted by phosphazene bases is reported. The reactions proceed smoothly, affording α,β-epoxy esters in nearly quantitative yields, short time, and no side products. The phosphazene base P1-t-Bu can be used with aldehydes carrying electron-withdrawing groups, while the base P4-t-Bu is preferable when the aldehydes carry electron
报道了磷腈碱促进的 α-卤代乙酸酯与芳香醛的第一个 Darzens 反应。反应进行顺利,以接近定量的收率、短时间得到α, β-环氧酯,且无副产物。磷腈碱P 1 - t -Bu可以与带有吸电子基团的醛一起使用,而当醛带有给电子取代基时,优选碱P 4 - t -Bu。