Van Hoveln Ryan, Hudson Brandi M, Wedler Henry B, Bates Desiree M, Le Gros Gabriel, Tantillo Dean J, Schomaker Jennifer M
†Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States.
‡Department of Chemistry, University of California, Davis, California 95616, United States.
J Am Chem Soc. 2015 Apr 29;137(16):5346-54. doi: 10.1021/ja511236d. Epub 2015 Apr 16.
An ongoing challenge in modern catalysis is to identify and understand new modes of reactivity promoted by earth-abundant and inexpensive first-row transition metals. Herein, we report a mechanistic study of an unusual copper(I)-catalyzed 1,3-migration of 2-bromostyrenes that reincorporates the bromine activating group into the final product with concomitant borylation of the aryl halide bond. A combination of experimental and computational studies indicated this reaction does not involve any oxidation state changes at copper; rather, migration occurs through a series of formal sigmatropic shifts. Insight provided from these studies will be used to expand the utility of aryl copper species in synthesis and develop new ligands for enantioselective copper-catalyzed halogenation.
现代催化领域中一个持续存在的挑战是识别和理解由储量丰富且价格低廉的第一行过渡金属促进的新反应模式。在此,我们报告了一项关于异常的铜(I)催化的2-溴苯乙烯1,3-迁移反应的机理研究,该反应将溴活化基团重新引入到最终产物中,同时使芳基卤键发生硼化反应。实验和计算研究相结合表明,该反应在铜上不涉及任何氧化态变化;相反,迁移是通过一系列形式上的σ迁移反应发生的。这些研究提供的见解将用于扩大芳基铜物种在合成中的应用,并开发用于对映选择性铜催化卤化反应的新配体。