Copper-Catalyzed<i>N</i>-Alkylation of Sulfonamides with Benzylic Alcohols: Catalysis and Mechanistic Studies
作者:Xinjiang Cui、Feng Shi、Man Kin Tse、Dirk Gördes、Kerstin Thurow、Matthias Beller、Youquan Deng
DOI:10.1002/adsc.200900490
日期:2009.11
N-alkylation of sulfonamides with alcohols is efficiently performed in the presence of easily available copper catalysts via hydrogen borrowing methodology. Applying a copper acetate/potassium carbonate system the reaction of sulfonamides and alcohols gave the corresponding secondary amines in excellent yield. In situ HR-MS analysis indicated that bissulfonylated amines are formed under air atmosphere
在容易获得的铜催化剂存在下,通过氢借用方法可有效地进行磺酰胺与醇的N-烷基化反应。采用乙酸铜/碳酸钾体系,磺酰胺和醇的反应以优异的产率得到了相应的仲胺。原位HR-MS分析表明,双磺酰化胺是在空气气氛下形成的,可作为催化体系的自稳定配体。紫外可见测量表明,铜中心与双磺酰化胺之间存在相互作用。苄醇-d 7与对甲苯磺酰胺,N-苄基-p的反应-甲苯磺酰胺或N-亚苄基棉烯磺酰胺表明反应是通过转移氢化机理进行的,整个过程是微可逆的。苄醇和苄醇的竞争反应d 7与p(-toluenesulfonamide揭示了动力学同位素效应ķ / H ķ的3.287(0.192)为苯甲醇的脱氢和0.611(0.033)为氢化d)ñ -亚苄基-对-甲苯磺酰胺中间体,这表明醇的脱氢是决定速率的步骤。