Department of Chemistry, School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
J Am Chem Soc. 2012 Aug 29;134(34):13970-3. doi: 10.1021/ja306934b. Epub 2012 Aug 13.
We have discovered a new class of cooperative catalytic system, consisting of heterogeneous polymer-immobilized bimetallic Pt/Ir alloyed nanoclusters (NCs) and 4-tert-butylcatechol, for the aerobic oxidation of amines to imines under ambient conditions. After optimization, the desired imines were obtained in good to excellent yields with broad substrate scope. The reaction rate was determined to be first-order with respect to the substrate and catechol and zero-order for the alloyed Pt/Ir NC catalyst. Control studies revealed that both the heterogeneous NC catalyst and 4-tert-butylcatechol are essential and act cooperatively to facilitate the aerobic oxidation under mild conditions.
我们发现了一类新的协同催化体系，由多相聚合物固载的双金属 Pt/Ir 合金纳米簇（NCs）和 4-叔丁基邻苯二酚组成，可在环境条件下实现胺的有氧氧化为亚胺。经过优化，以良好到优异的收率获得了所需的亚胺，底物范围广泛。反应速率被确定为底物和邻苯二酚的一级反应，以及合金化 Pt/Ir NC 催化剂的零级反应。对照研究表明，多相 NC 催化剂和 4-叔丁基邻苯二酚都是必需的，并协同作用以促进温和条件下的有氧氧化。
