The first example of a regioselective β-arylation of benzo[b]thiophenes and thiophenes at room temperature with aryl iodides as coupling partners is reported. This methodology stands out for its operational simplicity: no prefunctionalization of either starting material is required, the reaction is insensitive to air and moisture, and it proceeds at room temperature. The mild conditions afford wide
报道了苯并[b]噻吩和噻吩在室温下以芳基碘作为偶联伙伴的区域选择性β-芳基化的第一个例子。这种方法因其操作简单而突出:不需要任何一种起始材料的预官能化,反应对空气和水分不敏感,并且在室温下进行。温和的条件提供了广泛的官能团耐受性,通常具有完全的区域选择性和高产率,从而形成高效的催化系统。包括 13C 和 2H KIE 在内的初步机理研究表明,该过程是通过噻吩双键上的协同碳钯化作用发生的,然后是碱基辅助的抗消除作用。
Nickel-Catalyzed Asymmetric Hydrogenation of Cyclic Alkenyl Sulfones, Benzo[<i>b</i>]thiophene 1,1-Dioxides, with Mechanistic Studies
based on the cheap transition metal nickel for the asymmetric hydrogenation of challenging cyclic alkenyl sulfones, 3-substituted benzo[b]thiophene1,1-dioxides, was first successfully developed. A series of hydrogenation products, chiral 2,3-dihydrobenzo[b]thiophene1,1-dioxides, were obtained in high yields (95–99%) with excellent enantioselectivities (90–99% ee). According to the results of nonlinear
首次成功开发了一种基于廉价过渡金属镍的高效催化体系,用于挑战性环状烯基砜,3-取代的苯并[ b ]噻吩1,1-二氧化物的不对称加氢。以高收率(95-99%)和优异的对映选择性(90-99%ee)获得了一系列氢化产物,手性2,3-二氢苯并[ b ]噻吩1,1-二氧化物。根据非线性效应研究,氘标记实验和DFT计算研究的结果,为这种镍催化的不对称氢化提供了合理的催化机理,表明该氢化产物中两个加成的氢原子可能来自H 2。 通过插入Ni–H和随后的氢解反应。
Electrooxidative double C–H/C–H coupling of phenols with 3-phenylbenzothiophenes: facile access to benzothiophene derivatives
作者:Yuanyuan Yue、Junli Chao、Zhiyue Wang、Yan Yang、Yaqing Ye、Chunying Sun、Xiaohui Guo、Jianming Liu
DOI:10.1039/d1ob01208h
日期:——
double C–H/C–H coupling of phenols with 3-phenylbenzothiophene has been developed under external oxidant- and catalyst-free conditions. This strategy could enable the highly tunable access to benzothiophenederivatives and exhibited broad substrate generality under mild conditions. The reaction is likely to proceed via the cross-coupling of the p-methoxylphenol radical and the 3-phenylbenzothiophene radical
Selective Palladium-Catalysedipso Arylation of α,α-Disubstituted Benzo[b]thien-2-ylmethanols with Aryl Bromides using PCy3 as Ligand
作者:A. Beatrix Bíró、András Kotschy
DOI:10.1002/ejoc.200600929
日期:2007.3
α,α-Diphenylbenzo[b]thien-2-ylmethanol was treated with a series of arylbromides in the presence of palladium(II) acetate and tricyclohexylphosphane to give the appropriate 2-aryl-benzo[b]thiophenes in good to excellent yield with concomitant formation of benzophenone. The reaction wassuccessfully extended to α,α-diphenylbenzo[b]thien-3-ylmethanol, although in certain cases the transformation was
Palladium-Catalyzed Phosphine-Free Direct C–H Arylation of Benzothiophenes and Benzofurans Involving MIDA Boronates
作者:Mengmeng Huang、Yangjie Wu、Zhiwei Wang、Yabo Li、Beiqi Yan
DOI:10.1055/s-0034-1379606
日期:——
With high regioselectivity, a series of benzoheterocyclic compounds were synthesized via palladiium-catalyzed phosphine-free C-H arylation of benzothiophenes/benzofurans with aryl MIDA boronates at 30-50 degrees C in moderate to excellent yields. MIDA boronates were used in C-H arylation of heterocycles for the first time. Under the optimal conditions, the benzothiophenes could be transformed into the beta-arylbenzothiophenes, and the benzofurans gave only alpha-aryl-substituted products.