Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, Haus F, 81377 München, Germany.
Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland.
Org Lett. 2020 Mar 6;22(5):1899-1902. doi: 10.1021/acs.orglett.0c00238. Epub 2020 Feb 12.
We report the metalation of the 1,3,4-oxadiazole and 1,2,4-triazole scaffolds via regioselective zincation or magnesiation using the TMP bases (TMP = 2,2,6,6-tetramethylpiperidyl) TMPZn·2LiCl, TMPZn·2MgCl·2LiCl, TMPMgCl·LiCl, and TMPZnCl·LiCl under mild conditions in THF. Subsequent trapping with various electrophiles including hydroxylamino benzoates gives access to functionalized heterocycles while tolerating many functional groups.
我们报告了通过 TMP 碱(TMP = 2,2,6,6-四甲基哌啶)TMPZn·2LiCl、TMPZn·2MgCl·2LiCl、TMPMgCl·LiCl 和 TMPZnCl·LiCl 在温和条件下在 THF 中进行区域选择性锌化或镁化,实现 1,3,4-噁二唑和 1,2,4-三唑骨架的金属化。随后与各种亲电试剂(包括羟基氨基苯甲酸酯)进行捕获,可获得功能化的杂环,同时容忍许多官能团。