Iodine-Mediated Difunctionalization of Imidazopyridines with Sodium Sulfinates: Synthesis of Sulfones and Sulfides
作者:Yu-Jing Guo、Shuai Lu、Lu-Lu Tian、En-Ling Huang、Xin-Qi Hao、Xinju Zhu、Tian Shao、Mao-Ping Song
DOI:10.1021/acs.joc.7b02734
日期:2018.1.5
Novel iodine-induced sulfonylation and sulfenylation of imidazopyridines have been described using sodium sulfinates as the sulfur source. This strategy enables highly selective difunctionalization of imidazo[1,2-a]pyridine to access sulfones and sulfides in good yields. A wide range of substrates and functional groups were well-tolerated under optimized conditions. Moreover, control experiments have
已经描述了使用亚磺酸钠作为硫源的新的碘诱导的咪唑并吡啶的磺酰化和亚磺酰化。该策略能够使咪唑并[1,2- a ]吡啶高度选择性地进行双官能化,从而以高收率获得砜和硫化物。在最佳条件下,各种底物和官能团均具有良好的耐受性。此外,已经进行了对照实验,表明了反应机理中涉及的自由基途径。
Dual role of p-tosylchloride: copper-catalyzed sulfenylation and metal free methylthiolation of imidazo[1,2-a]pyridines
imidazo[1,2-a]pyridines using p-tosylchloride as a benign source of sulfenylating agents has been developed. On the other hand, p-tosylchloride mediated thiomethylation of imidazo[1,2-a]pyridines with dimethylsulfoxide as a source of thiomethylation under metal-free conditions was also described.
已经开发了使用对甲苯磺酰氯作为亚磺化剂的良性来源的咪唑并[1,2- a ]吡啶的铜催化的区域选择性C-3亚磺酰基化。另一方面,还描述了在无金属条件下,对甲苯磺酰氯介导的咪唑并[1,2- a ]吡啶的硫甲基化,其中使用二甲基亚砜作为硫甲基化的来源。
Molecular iodine enabled generation of iminyl radicals from oximes: A facile route to imidazo[1,2-a]pyridines and its regioselective C-3 sulfenylated products from simple pyridines
作者:Deepak Singh、Soumyadeep Roy Chowdhury、Shyamal Pramanik、Soumitra Maity
DOI:10.1016/j.tet.2021.132125
日期:2021.5
2-a]pyridinesfrom unfunctionalized pyridines and oxime esters. This straightforward method efficiently converts the substrates into corresponding products affording moderate to good yields with large functional group tolerance. Additionally extensive investigation revealed that regioselective domino C-3 methyl sulfenylated imidazo[1,2-a]pyridines were also accessible first time frompyridines and
已经开发了碘促进的简单且环境友好的方案,以从未官能化的吡啶和肟酯中获得咪唑并[1,2- a ]吡啶。这种简单的方法可以有效地将底物转化为相应的产品,从而提供中等到良好的产率以及较大的官能团耐受性。另外,广泛的研究表明,在DMSO溶剂中,吡啶和肟酯类也可以首次获得区域选择性多米诺C-3甲基亚磺酰咪唑并[1,2- a ]吡啶。该反应通过容易获得的肟酯的无金属生成亚胺基进行,从而在吡啶上建立第二个杂环。
I<sub>2</sub>–DMSO–PTSA: a simple and metal free oxidative cross coupling of imidazo[1,2-a]pyridines and methylketones
simple, highly efficient and selective oxidative cross coupling of imidazo[1,2-a]pyridine (IP) compounds (1) and methylketones (2), promoted by molecular iodine in DMSO in the presence of a catalytic amount of PTSA has been realized in a one pot reaction. This strategy has provided a general route for the synthesis of 1-aryl-2-(2-phenylimidazo[1,2-a]pyridin-3-yl)ethane-1,2-diones (3) with a new C–C bond
在催化量的PTSA存在下,由分子碘在DMSO中促进的咪唑并[1,2- a ]吡啶(IP)化合物(1)和甲基酮(2)的简单,高效且选择性的氧化交叉偶联已经被发现。一锅反应。该策略为用新的CC合成1-芳基-2-(2-苯基咪唑并[1,2 - a ]吡啶-3-基)乙烷-1,2-二酮(3)提供了一般路线。通过Kornblum氧化形成键,然后在原位形成的苯乙二醛上进行IP化合物(1)的亲核攻击。简单的反应条件,无金属催化剂和选择性的产物形成是该方案的优点。
Iodine-catalyzed regioselective thiolation of imidazo[1,2-a]pyridines using sulfonyl hydrazides as a thiol surrogate
sulfenylation of imidazo[1,2-a]pyridines via C(sp(2))-H bondfunctionalization has been achieved using sulfonyl hydrazides as a thiol surrogate. A library of 3-sulfanylimidazopyridines with broad functionalities was synthesized under metal and oxidant-free practical reaction conditions. This methodology is also applicable for the regioselective sulfenylation of imidazo[2,1-b]thiazole and benzo[d]imidazo[2,1-b]thiazole