Dastbaravardeh Navid, Schnürch Michael, Mihovilovic Marko D
Institute of Applied Synthetic Chemistry, Vienna University of Technology Getreidemarkt 9/163-OC, 1060 Vienna, Austria.
European J Org Chem. 2013 May;2013(14):2878-2890. doi: 10.1002/ejoc.201300004. Epub 2013 Mar 22.
The ruthenium(II)-catalyzed sp C-H bond arylation of benzylic amines with aryl halides is reported. In the present method, aryl iodides and, more importantly, also the cheaper aryl bromides and aryl chlorides can be applied as aryl sources. Additionally, the method does not require elaborate manipulations in a glove box and can be carried out in simple screw cap vials. Potassium pivalate proved to be beneficial for the transformation with aryl bromides or iodides as aryl source, but was not required for aryl chlorides. In the latter case, the addition of PPh led to high conversion. 3-Methyl and 3-phenyl pyridine were established as directing groups, and the substituent in the 3-position represents a key structural feature for high conversion. The directing group can be cleaved after the transformation, which allows access to diarylmethylamines. Mechanistic studies were carried out and critically compared to mechanistic reports of related transformations.
报道了钌（II）催化苄胺与芳基卤化物的sp C-H键芳基化反应。在本方法中，芳基碘化物，更重要的是，更便宜的芳基溴化物和芳基氯化物都可以用作芳基源。此外，该方法不需要在手套箱中进行精细操作，可以在简单的螺帽小瓶中进行。事实证明，新戊酸钾有利于以芳基溴化物或碘化物作为芳基源的转化，但对于芳基氯化物则不需要。在后一种情况下，添加三苯基膦可实现高转化率。3-甲基吡啶和3-苯基吡啶被确定为导向基团，3-位的取代基是实现高转化率的关键结构特征。导向基团在转化后可以裂解，从而得到二芳基甲胺。进行了机理研究，并与相关转化的机理报告进行了严格比较。
