H<sub>2</sub>O<sub>2</sub>/DMSO-Promoted Regioselective Synthesis of 3,3′-Bisimidazopyridinylmethanes via Intermolecular Oxidative C(sp<sup>2</sup>)–H Bond Activation of Imidazoheterocycles
作者:Om P. S. Patel、Devireddy Anand、Rahul K. Maurya、Prem P. Yadav
DOI:10.1021/acs.joc.6b01355
日期:2016.9.2
under air. A library of 3,3′-bis(2-arylimidazo[1,2-a]pyridin-3-yl)methanes has been achieved in good to excellent yields. The present methodology has been successfully applied to imidazo[2,1-b]thiazoles and imidazo[2,1-b]benzothiazoles. Furthermore, the current approach was also extended for the synthesis of unsymmetrical 3,3′-bisimidazopyridinylmethanes under optimized reaction conditions. A mechanistic
在过去的十年中,无金属的C–C键形成方法因其易用性和低成本而备受关注。该报告代表了一种新的,无金属的3,3'-双咪唑并吡啶甲基甲烷的合成方法,该方法是通过咪唑并[1,2- a ]吡啶的分子间氧化C(sp 2)-H键分子间氧化,并以二甲基亚砜作为碳合成子(CH 2)在空气中使用H 2 O 2作为温和的氧化剂。已经获得了3,3'-双(2-芳基咪唑并[1,2- a ]吡啶-3-基)甲烷的文库,收率良好至极佳。本方法已成功地应用于咪唑并[2,1- b ]噻唑和咪唑并[2,1- b]苯并噻唑。此外,当前的方法也扩展到在优化的反应条件下合成不对称的3,3'-双咪唑并吡啶基甲烷。根据自由基清除剂的实验,DMSO- d 6和ESI-MS的观察结果,提出了一种机理途径。