Manganese catalyzed C–H functionalization of indoles with alkynes to synthesize bis/trisubstituted indolylalkenes and carbazoles: the acid is the key to control selectivity
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.
Metal-Free Indole–Phenacyl Bromide Cyclization: A Regioselective Synthesis of 3,5-Diarylcarbazoles
作者:Sudipto Debnath、Tuluma Das、Tanmay K. Pati、Swapan Majumdar、Dilip K. Maiti
DOI:10.1021/acs.joc.0c01670
日期:2020.10.16
A metal-free, simultaneous triple C–C coupling cyclization reaction between phenacyl bromides and indoles is discovered in a highly regioselective fashion to furnish 3,5-diarylcarbazoles. DMAP is utilized as the only reagent for the unusual and rapid cyclization reaction to furnish all new carbazole compounds through installation of a great diversity of substituents. A plausible radical mechanism for
One-pot access to tetrahydrobenzo[<i>c</i>]carbazoles from simple ketones by using O<sub>2</sub> as an oxidant
作者:Shuvendu Saha、Modhu Sudan Maji
DOI:10.1039/c9ob02751c
日期:——
diversely functionalized carbazole frameworks starting from protecting group free 2-alkenyl indoles. The employment of easily available unactivated ketones as annulating partners, mostly unexplored for the synthesis of carbazoles, is the major highlight of this protocol. This protocol is step- and atom-economical, uses molecular oxygen as the green oxidant, and gives water as the only by-product and is amenable
Gold-Catalyzed Sequential Alkyne Activation: One-Pot Synthesis of NH-Carbazoles via Cascade Hydroarylation of Alkyne/6-Endo-Dig Carbocyclization Reactions
作者:Srinivas Samala、Anil K. Mandadapu、Mohammad Saifuddin、Bijoy Kundu
DOI:10.1021/jo400799b
日期:2013.7.5
efficient one-pot protocol for the synthesis of NH-carbazoles has been described. The strategy comprises a one-pot reaction involving the treatment of 2-alkynyl indoles with arylacetylenes in the presence of an Au–Ag combination catalyst. The salient feature of the strategy involves sequential activation of terminal and internal alkynes leading to the cascade hydroarylation of terminal alkynes and 6-endo-dig
Gold-catalyzed benzannulations of 2-alkenylindoles with alkynes: a protecting-group-free regioselective approach to carbazoles
作者:Pathan Mosim Amin、Weilin Wang、Chao Wang、Junrui Zhou、Youliang Wang
DOI:10.1039/d4cc00176a
日期:——
A gold(I)-catalyzed protecting-group-free benzannulation approach to functionalized NH-carbazoles was accomplished via the hydroarylation of alkynes with 2-alkenylindoles. A broad spectrum of terminal and internal alkynes and 2-alkenylindoles successfully participated in this annulation reaction. The protocolefficiently enabled the formation of substituted NH-carbazoles with moderate to specific regioselectivities
通过炔烃与 2-烯基吲哚的加氢芳基化,实现了金 ( I ) 催化的无保护基苯并环化方法,得到功能化 NH-咔唑。多种末端炔烃和内部炔烃以及 2-烯基吲哚成功地参与了该环化反应。该方案有效地形成了具有中等至特定区域选择性的取代 NH-咔唑。该协议的合成实用性通过各种后功能化得到了证明。