Metal-Free Double Csp2–H Bond Functionalization: Strategy for Synthesizing Benzo[a]carbazoles from 2-Arylindoles and Acetophenones/Alkynes
摘要:
A metal-free strategy for the synthesis of benzocarbazoles from 2-arylindoles and aryl ketones is developed. Various 2-aryl-3-vinyl-indoles were generated in situ through dehydrative condensation of aryl ketones and indoles. These key intermediates could be selectively converted into the corresponding benzo[a]carbazoles via a direct cyclization process between two Csp(2)-H bonds. Furthermore, terminal alkynes also could be used as the versatile C2 source to afford the corresponding products in good yields.
atom-economical synthetic method for the generation of fused indoles, using a gold-catalyzedcascadecyclization of diynes, has been developed. The reaction gave various fused indoles, such as aryl-annulated[a]carbazoles, dihydrobenzo[g]indoles, and azepino- or oxepinoindole derivatives in good to excellent yields, through an intramolecular cascade 5-endo-dig hydroamination followed by a 6- or 7-endo-dig cycloisomerization
已经开发了一种直接,简洁且原子经济的合成方法,该方法使用金催化的二炔级联环化生成稠合的吲哚。该反应通过分子内级联5-内-挖-加氢胺化,然后进行6-氨基苯甲酸酯化,得到了各种稠合的吲哚,例如芳基环化的[ α ]咔唑,二氢苯并[ g ]吲哚和氮杂环庚烷-或氧代庚并吲哚衍生物,收率良好。或7-内挖式环异构化,而不会产生理论副产物。所得的三支吲哚对T表现出有效的抗真菌活性。癣菌和Ť。风疹,说明了所描述的级联反应在药物发现中的实际应用。
Gold-Catalyzed Intramolecular Alkyne Cycloisomerization Cascade: Direct Synthesis of Aryl-Annulated[<i>a</i>]carbazoles from Aniline-Substituted Diethynylarenes
Aniline-substituteddiethynylarenes, which are readily synthesized through Sonogashira coupling reactions from commercially available 1,2-dihaloarenes, directly produce aryl- and heteroaryl-annulated[a]carbazoles by the gold-catalyzedintramolecularcascade hydroamination/cycloisomerization without producing theoretical by-products. This new atom-economical route is easily applicable to various ar
苯胺取代的二乙炔基很容易通过Sonogashira偶联反应由市售的1,2-二卤代芳烃合成,通过金催化的分子内级联加氢胺化/环异构化反应直接生成芳基和杂芳基环化的[ a ]咔唑,而不会产生理论副产物。 。这种新的原子经济的路线是容易地应用于各种芳基-环[一]咔唑含有烷基,芳基或酯取代基。
Copper-catalyzed synthesis of benzocarbazoles via α-C-arylation of ketones
作者:Ruilong Xie、Yun Ling、Hua Fu
DOI:10.1039/c2cc36403d
日期:——
A simple and efficient copper-catalyzed method for the synthesis of 11H-benzo[a]carbazoles has been developed. The protocol uses readily available substituted 2-(2-bromophenyl)-1H-indoles and ketones as starting materials and an inexpensive catalyst system. The corresponding 11H-benzo[a]carbazoles were obtained in moderate to excellent yields.
Synthesis of Benzo[<i>a</i>]carbazole Derivatives from β-(2-Arylindolyl)nitroalkanes via Mn(OAc)<sub>3</sub>-mediated Cyclization
作者:Su Yeon Kim、Jin Woo Lim、Beom Kyu Min、Jae Nyoung Kim
DOI:10.1002/bkcs.10989
日期:2016.11
and coppercatalyzed synthesis via α-C-arylation of ketones. Recently, we also reported the synthesis of benzo[a]carbazoles from 2-arylindoles via sequential propargylation, propargyl–allenyl isomerization, and 6π-electrocyclization approach, as shown in Scheme 1. Various 5-benzyland 5-methylbenzo[a]carbazoles have been synthesized; however, 5-unsubstituted benzo[a]carbazoles could not be synthesized