Metal- and base-free regioselective thiolation of the methyl C(sp<sup>3</sup>)–H bond in 2-picoline <i>N</i>-oxides
作者:Dong Wang、Zhenlin Liu、Zhentao Wang、Xinyue Ma、Peng Yu
DOI:10.1039/c8gc03072c
日期:——
A one-pot, two-step synthesis of pyridine-2-ylmethyl thioethers is developed through a TFAA-mediated [3,3]-sigmatropic rearrangement of pyridine N-oxides and TBAB-catalyzed direct conversion of trifluoroacetates into thioethers under metal- and base-free conditions. This methodology enables thiolation of the unactivated methyl C(sp3)–H bond in 2-picolines with thiols. Remarkable features of the method
通过TFAA介导的吡啶N-氧化物的[3,3]-σ重排和TBAB催化的三氟乙酸盐在金属和金属催化下直接转化为三氟乙酸的反应,可以开发一锅两步的吡啶-2-基甲基硫醚合成方法无碱条件。这种方法可以使未活化的甲基C(sp 3硫醇化)–2-甲基吡啶与硫醇的氢键。该方法的显着特征包括区域选择性高,阶跃和原子经济,条件温和,操作简单,底物范围广和可扩展性。此外,该方法已成功地用于合成奥美拉唑硫化物和雷贝拉唑硫化物,而无需TBAB催化。全面的绿色化学指标分析表明,该方法比报道的雷贝拉唑硫化物更有效,更环保。