Low-Temperature, Transition-Metal-Free Cross-Dehydrogenative Coupling Protocol for the Synthesis of 3,3-Disubstituted Oxindoles
作者:James R. Donald、Richard J. K. Taylor、Wade F. Petersen
DOI:10.1021/acs.joc.7b02085
日期:2017.10.20
strong, nonreversible base in these reactions has been found to effect a dramatic drop in reaction temperature (to room temperature) relative to the current state-of-the-art (>100 °C) procedure. When employing iodine as an “oxidant”, new evidence suggests that this transformation may occur via a transiently stable iodinated intermediate rather than by direct single-electron oxidation.
报道了一种通过交叉脱氢偶联(CDC)合成3,3-二取代的2-氧吲哚的新的低温程序。已经发现在这些反应中使用强的,不可逆的碱会导致反应温度相对于当前的最新技术水平(> 100°C)急剧下降(降至室温)。当使用碘作为“氧化剂”时,新证据表明,这种转变可能是通过暂时稳定的碘化中间体而不是直接的单电子氧化而发生的。