Lewis Acid Promoted Aerobic Oxidative Coupling of Thiols with Phosphonates by Simple Nickel(II) Catalyst: Substrate Scope and Mechanistic Studies
作者:Jing-Wen Xue、Miao Zeng、Sicheng Zhang、Zhuqi Chen、Guochuan Yin
DOI:10.1021/acs.joc.9b00194
日期:2019.4.5
Exploring new catalysts for efficient organic synthesis is among the most attractive topics in chemistry. Here, using Ni(OAc)2/LA as catalyst (LA: Lewis acid), a novel catalyst strategy was developed for oxidative coupling of thiols and phosphonates to phosphorothioates with oxygen oxidant. The present study discloses that when Ni(OAc)2 alone was employed as the catalyst, the reaction proceeded very
探索新的催化剂以进行有效的有机合成是化学领域中最具吸引力的主题之一。在这里,使用Ni(OAc)2 / LA作为催化剂(LA:路易斯酸),开发了一种新的催化剂策略,用于用氧氧化剂将硫醇和膦酸酯氧化偶联为硫代磷酸酯。本研究揭示了当单独使用Ni(OAc)2作为催化剂时,反应进行缓慢,收率低,而向Ni(OAc)2中添加了Y 3+等非氧化还原活性金属离子。大大提高了其催化效率。促进作用是高度路易斯酸度,取决于添加的路易斯酸,通常,较强的路易斯酸可提供更好的促进作用。停止流动力学证实添加Y(OTf)3可以明显加速Ni(II)对硫醇的活化,然后加速其与膦酸酯的反应以生成硫代磷酸酯产物。催化剂的ESI-MS表征揭示了在催化剂溶液中异双金属Ni(II)/ Y(III)物种的形成。另外,该Ni(II)/ LA催化剂可用于合成包括几种商业生物活性化合物的一系列硫代磷酸酯化合物。该催化剂策略明确支持路易斯酸可以显