Mechanistic Investigations and Substrate Scope Evaluation of Ruthenium-Catalyzed Direct sp3 Arylation of Benzylic Positions Directed by 3-Substituted Pyridines
摘要:
A highly efficient direct arylation process of benzylic amines with arylboronates was developed that employs Ru catalysis. The arylation takes place with greatest efficiency at the benzylic sp(3) carbon. If the distance to the activating aryl ring is increased, arylation is still possible but the yield drops significantly. Efficiency of the CH activation was found to be significantly increased by use of 3-substituted pyridines as directing groups, which can be removed after the transformation in high yield. Calculation of the energy profile of different rotamers of the substrate revealed that presence of a substituent in the 3-position favors a conformation with the CH2 group adopting a position in closer proximity to the directing group and facilitating C-H insertion. This operationally simple reaction can be carried out in argon atmosphere as well as in air and under neutral reaction conditions, displaying a remarkable functional group tolerance. Mechanistic studies were carried out and critically compared to mechanistic reports of related transformations.
Aryl Bromides and Aryl Chlorides for the Direct Arylation of Benzylic Amines Mediated by Ruthenium(II)
作者:Navid Dastbaravardeh、Michael Schnürch、Marko D. Mihovilovic
DOI:10.1002/ejoc.201300004
日期:2013.5
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
The present invention relates to compounds having the structure useful as potassium channel inhibitors to treat cardiac arrhythmias, and the like.
本发明涉及具有结构的化合物,可用作钾通道抑制剂以治疗心律失常等。
US7345068B2
申请人:——
公开号:US7345068B2
公开(公告)日:2008-03-18
US8148535B2
申请人:——
公开号:US8148535B2
公开(公告)日:2012-04-03
Mechanistic Investigations and Substrate Scope Evaluation of Ruthenium-Catalyzed Direct sp<sup>3</sup> Arylation of Benzylic Positions Directed by 3-Substituted Pyridines
作者:Navid Dastbaravardeh、Karl Kirchner、Michael Schnürch、Marko D. Mihovilovic
DOI:10.1021/jo302547q
日期:2013.1.18
A highly efficient direct arylation process of benzylic amines with arylboronates was developed that employs Ru catalysis. The arylation takes place with greatest efficiency at the benzylic sp(3) carbon. If the distance to the activating aryl ring is increased, arylation is still possible but the yield drops significantly. Efficiency of the CH activation was found to be significantly increased by use of 3-substituted pyridines as directing groups, which can be removed after the transformation in high yield. Calculation of the energy profile of different rotamers of the substrate revealed that presence of a substituent in the 3-position favors a conformation with the CH2 group adopting a position in closer proximity to the directing group and facilitating C-H insertion. This operationally simple reaction can be carried out in argon atmosphere as well as in air and under neutral reaction conditions, displaying a remarkable functional group tolerance. Mechanistic studies were carried out and critically compared to mechanistic reports of related transformations.