Efficient Syntheses of 2,5-Dihydropyrroles, Pyrrolidin-3-ones, and Electron-Rich Pyrroles from<i>N</i>-Tosylimines and Lithiated Alkoxyallenes
作者:Ghislaine Marlyse Okala Amombo、Oliver Flögel、Scheghajeh Kord Daoroun Kalai、Stefan Schoder、Ulrike Warzok、Hans-Ulrich Reissig
DOI:10.1002/ejoc.201700073
日期:2017.4.10
The addition of lithiated alkoxyallenes to N‐tosylimines followed by base‐, silver‐, or gold‐promoted cyclization of the addition products efficiently provides 2,5‐dihydropyrroles, which are excellent substrates for further transformations. Acids promote the hydrolysis of the enol ether moiety to deliver pyrrolidin‐3‐ones, and bases promote the aromatization to the elusive 3‐alkoxypyrroles.
在N-甲苯磺胺中添加锂化的烷氧基丙二烯,然后通过碱,银或金促进的加成产物环化,可有效地提供2,5-二氢吡咯,这是进行进一步转化的极佳底物。酸促进烯醇醚部分的水解以提供吡咯烷-3-酮,而碱则促进芳香化至难以捉摸的3-烷氧基吡咯。