Selectivity Control in Gold-Catalyzed Hydroarylation of Alkynes with Indoles: Application to Unsymmetrical Bis(indolyl)methanes
摘要:
Gold-catalyzed hydroarylation of unactivated alkynes with indoles have previously been reported to proceed with double indole addition to produce symmetrical bis(indolyl)methanes (BIMs). We demonstrate for the first time that the selectivity of the gold-catalyzed reaction can be fully switched to allow for isolation of the vinylindole products instead. Furthermore, this selective reaction can be utilized to synthesize the more difficult to access unsymmetrical BIMs from readily available starting materials.
Metal‐Free Three‐Component Selenopheno[2,3‐
<i>b</i>
]indole Formation through Double C−H Selenylation with Selenium Powder
作者:Penghui Ni、Jing Tan、Wenqi Zhao、Huawen Huang、Guo‐Jun Deng
DOI:10.1002/adsc.201901023
日期:2019.12.3
A facile metal‐free entry to novel selenopheno[2,3‐b]indole motif is described. The three‐component assembly of indoles, aromatic ketones, and seleniumpowder is enabled by the IBr‐promoted highly selective doubleC–Hselenylation/annulation. This protocol provides a novel access to a diverse variety of selenopheno[2,3‐b]indoles with good efficacy and broad functional group compatibility.
描述了一种新颖的硒代苯并[2,3- b ]吲哚基序的无金属入口。吲哚,芳族酮和硒粉的三组分组装是由IBr促进的高选择性双C–H硒化/环化反应实现的。该协议提供了一种新颖的途径来获得具有良好疗效和广泛的官能团相容性的硒硒酚[2,3- b ]吲哚。
Indole-to-Carbazole Strategy for the Synthesis of Substituted Carbazoles under Metal-Free Conditions
作者:Shanping Chen、Yuxia Li、Penghui Ni、Huawen Huang、Guo-Jun Deng
DOI:10.1021/acs.orglett.6b02762
日期:2016.10.21
An efficient indole-to-carbazole strategy has been developed under metal-free conditions. This carbazole formation was highly promoted by NH4I with high regioselectivity through formal [2 + 2 + 2] annulation of indoles, ketones, and nitroolefins. It thus conveniently enabled the assembly of a large number of diversified carbazole products with good tolerance of a broad range of functional groups.
Three-Component Cascade Synthesis of Carbazoles through [1s,6s] Sigmatropic Shift under Metal-Free Conditions
作者:Shanping Chen、Pingyu Jiang、Pu Wang、Yong Pei、Huawen Huang、Fuhong Xiao、Guo-Jun Deng
DOI:10.1021/acs.joc.8b02994
日期:2019.3.15
A novel method was developed for the synthesis of substituted carbazoles from commercially available starting materials under metal-free conditions. This strategy involves a [1s,6s] sigmatropic shift step and introduces an electron-withdrawing ester substituent at the C2 position of the carbazole ring. The present protocol afforded the desired carbazole derivatives with good regioselectivity and well
A highly efficient alkenylation reaction of arylglyoxals with 3-vinylindoles catalyzed by chiral calciumphosphate is described. Structurally diverse allylic alcohols bearing indole and carbonyl units are prepared in excellent yields, good diastereoselectivities, and high to excellent enantioselectivities. These products are good building blocks for the synthesis of polysubstituted chiral tetrahydrocarbozol-2-ones
TfOH-Catalyzed One-Pot Domino Reaction for Diastereoselective Synthesis of Polysubstituted Tetrahydrospiro[carbazole-1,3′-indoline]s
作者:Ren-Yin Yang、Jing Sun、Yao Tao、Qiu Sun、Chao-Guo Yan
DOI:10.1021/acs.joc.7b02397
日期:2017.12.15
one-pot sequential reaction of indoles, acetophenones (cyclic ketones), and various 3-methyleneoxindolines in toluene afforded polysubstituted tetrahydrospiro[carbazole-1,3′-indoline]s in satisfactory yields. 1H NMR spectra and single-crystal structures indicated that the obtained tetrahydrospiro[carbazole-1,3′-indoline]s existing in an unusual trans-configuration. The reaction mechanism was believed
TfOH催化的吲哚,苯乙酮(环酮)和各种3-亚甲基二氢吲哚在甲苯中的一锅顺序反应可得到令人满意的多取代四氢螺环[咔唑-1,3'-二氢吲哚] s。1 H NMR谱和单晶结构表明,所获得的四氢螺[[咔唑-1,3'-二氢吲哚]以不寻常的反式构型存在。据认为,该反应机理是通过吲哚与苯乙酮的吲哚的多核苷酸催化3-烯基化,3-烯基吲哚与3-亚甲基二氧吲哚的狄尔斯-阿尔德反应以及酸催化的非对映异构化过程来进行的。