A convenient [hydroxy(tosyloxy)iodo]benzene-mediated one-pot synthesis of 2-arylimidazo[2,1-b]benzothiazoles
摘要:
Several 2-arylimidazo[2,1-b]benzothiazoles (4) have been conveniently synthesized in one-pot reactions via alpha-tosyloxylation of enolizable ketones (1) using [hydroxy(tosyloxy)iodo]benzene 2 in acetonitrile, followed by treatment with 2-amino-6-(substituted)benzothiazoles (3). The present protocol offers several advantages towards general access of 2-arylimidazo[2,1-b]benzothiazoles, including an intriguing alternative to the literature protocols, a readily available nontoxic reagent, operational simplicity and an environmentally benign procedure.
Visible-light-induced photocatalytic difluoroacetylation of imidazopyridines via direct and regioselective C H functionalization
作者:Guojie Yin、Mei Zhu、Weijun Fu
DOI:10.1016/j.jfluchem.2017.04.005
日期:2017.7
A visible-light-mediated direct and regioselective difluoroacetylation reaction of imidazoheterocycles by using BrCF2CO2Et under mild reaction conditions has been developed. With the utilization of a highly active CF2CO2Et radical, the developed photocatalytic method enables the introduction of a CF2CO2Et group in an efficient and regioselective reaction through CH bond functionalization with high
利用BrCF 2 CO 2 Et在温和的反应条件下开发了咪唑杂环的可见光直接和区域选择性二氟乙酰化反应。通过利用高活性的CF 2 CO 2 Et自由基,开发的光催化方法能够通过具有高官能团耐受性的C H键官能化在高效和区域选择性反应中引入CF 2 CO 2 Et基团。
Electrochemical sulfonylation of imidazoheterocycles under batch and continuous flow conditions
protocol for the C–H sulfonylation of imidazoheterocycles via electrochemical activation was established under batch and flow conditions. The selective C–Hbondfunctionalization proceeded under catalyst- and oxidant-free conditions and tolerated a wide range of functional groups. Various sodium sulfinates as well as imidazo[1,2-a]-pyridines, -pyrimidine, -quinolines, and -isoquinolines, imidazo[1,2-b]pyridazine
在分批和流动条件下,建立了一种通过电化学活化对咪唑杂环进行 C-H 磺酰化的有效且通用的方案。选择性 C-H 键官能化在无催化剂和无氧化剂条件下进行,并耐受多种官能团。各种亚磺酸钠以及咪唑并[1,2- a ]-吡啶、-嘧啶、-喹啉和-异喹啉、咪唑并[1,2- b ]哒嗪、咪唑[2,1- b ]噻唑和苯并[ d ]咪唑并[1,2- b ]噻唑反应成功。有趣的是,在微流体条件下获得了显着的加速和更高的产量。
Metal-Free Oxidative Deamination Cross-Coupling of Imidazoheterocycles with 2-Aminobenzothiazoles
metal-free oxidative deamination–cross-coupling of imidazoheterocycles with 2-aminobenzothiazoles in the presence of tert-butyl nitrite is reported for the first time. This simple protocol tolerates a wide range of functional groups to afford various benzothiazole–imidazoheterocycles in moderate to excellent yields, with the release of nitrogen and water as benign byproducts. A metal-free oxidative deam
A visible light-mediated regioselective C3-ethoxycarbonylmethylation of imidazopyridines with ethyl diazoacetate (EDA) was achieved under mild reaction conditions. In contrast to the carbene precursors from α-diazoester a first C3-ethoxycarbonylmethylation of imidazopyridines via a radical intermediate has been established. The present methodology provides a concise route to access pharmacologically
Electrochemical-induced regioselective C-3 thiomethylation of imidazopyridines <i>via</i> a three-component cross-coupling strategy
作者:Jiangwei Wen、Cong Niu、Kelu Yan、Xingda Cheng、Ruike Gong、Mengqian Li、Yongqiang Guo、Jianjing Yang、Hua Wang
DOI:10.1039/c9gc04068d
日期:——
The electrochemical-induced regioselective C-3 thiomethylation of imidazopyridines has been initially accomplished via a three-component cross-coupling strategy using thiocyanate as the sulfur source and methanol as the methyl reagent. This protocol provides a green method for the thiomethylation of imidazopyridines without the need for any exogenous oxidants and metal catalysts under room temperature