Cleavage of C–C Bonds for the Synthesis of C2-Substituted Quinolines and Indoles by Catalyst-Controlled Tandem Annulation of 2-Vinylanilines and Alkynoates
作者:Jixiang Ni、Yong Jiang、Zhenyu An、Rulong Yan
DOI:10.1021/acs.orglett.8b00260
日期:2018.3.16
and alkynoates through C–C bond cleavage is developed. With these general methods, 2-substituted indoles and quinolines can be accessed via tandem Michael addition and cyclization with no requirement of oxidant. This strategy not only provides a method for the synthesis C2-substituted indoles in good yields through the simultaneous cleavage of C═C and C≡C bonds under metal-free conditions but also provides
tert-Butyl nitrite (TBN) as the N atom source for the synthesis of substituted cinnolines with 2-vinylanilines and a relevant mechanism was studied
作者:XiaoBo Pang、LianBiao Zhao、DaGang Zhou、Ping Yong He、ZhenYu An、Ji Xiang Ni、RuLong Yan
DOI:10.1039/c7ob01553d
日期:——
A green method to synthesize cinnolines by 6π electrocyclic reaction with alkenyl amines and TBN has been developed. TBN plays a dual role both as the nitrogen atom source and oxidant in this procedure. Relevant mechanism experiments reveal the reaction proceeds through electrocyclic reaction and with diazo hydroxide as a key intermediate.
Carbon annulation of ortho-vinylanilines with dimethyl sulfoxide to access 4-aryl quinolines
作者:Jin Yuan、Jin-Tao Yu、Yan Jiang、Jiang Cheng
DOI:10.1039/c6ob02714h
日期:——
A palladium-catalyzed annulation of ortho-vinylanilines with dimethylsulfoxide was developed to access 4-aryl quinolines in moderate to good yields. Activated by 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) adduct (DABSO), DMSO served as a “CH–” fragment in this transformation. It represents a facile pathway leading to 4-aryl quinolines.
A palladium‐catalyzed [5+1] annulation of 2‐(1‐arylvinyl) anilines and α‐diazocarbonyl compounds has been developed, affording a series of multi‐functionalized quinolines in moderate to good yields. This procedure proceeded with the sequential insertion of N−H bond to the palladium carbene, intramolecular Heck reaction and decarboxylation steps. In this reaction, alkyl 2‐diazophenylacetates served
Brønsted Acid-Catalyzed Synthesis of<i>N</i>-Arylindoles from 2-Vinylanilines and Quinones
作者:Han-Ming Zhang、Zhong-Hua Gao、Liang Yi、Song Ye
DOI:10.1002/asia.201600420
日期:2016.10.6
In the presence of a quinone, Brønstedacid‐catalyzed intramolecular C−N bond formation of o‐vinylanilines by electrophilic cyclization was developed, giving the corresponding N‐arylindoles in good to high yields. The reaction worked well for o‐vinylanilines with terminal and internal C=C double bonds.