报道了丙二酸亚丙二酸酯与吲哚的新型环化反应,它可有效地获得各种六氢咔唑。对映选择性形式是通过微调的配体/ Cu II催化剂实现的。光学活性的六氢咔唑包含三个季碳中心,并以高达99%的收率和大于99:1的dr以及高达大于99%的ee获得。该反应可以以克为单位进行,产物的立体选择性转化导致了来自Kopsia植物的一系列生物碱的核心结构。
Visible Light-Mediated C–H Difluoromethylation of Electron-Rich Heteroarenes
作者:Yi-Ming Su、Yu Hou、Feng Yin、Yue-Ming Xu、Yan Li、Xiaoqi Zheng、Xi-Sheng Wang
DOI:10.1021/ol501094z
日期:2014.6.6
A novel method for visible-light photoredox-catalyzed difluoromethylation of electron-rich N-, O-, and S-containingheteroarenes under mild reaction conditions is developed. Mechanistic investigation indicates that the net C–H difluoromethylation proceeds through an electrophilic radical-type pathway.