The reaction of α-substituted 2-isocyanostyrenes, which could be readily prepared from commercially available 2-aminophenyl ketones or 2-aminobenzonitriles, with sulfur in the presence of a catalytic amount of selenium proceeded smoothly to give the corresponding 2-isothiocyanatestyrenes. The latter spontaneously underwent the electrocyclic reaction to afford 4-substituted quinoline-2(1H)-thiones in one-pot with isolated yields ranging from 37 to 91%.
A novel quinoline synthesis starting with 2-isocyanostyrene derivatives is described. The treatment of 2-isocyanostyrene derivatives with aldehydes (or acetone) in the presence of a catalytic amount of diethyl ether-borontrifluoride afforded quinolinederivatives carrying a 1-hydroxyalkyl substituent at the 2-position. The use of acetaldehyde diethyl acetal or phenyloxirane as an electrophile under
Iodine‐Mediated Regioselective Radical Cyclization of <i>o</i>‐Vinylaryl Isocyanides with Disulfides/Diselenides Leading to 2‐Chalcogenated Quinolines
作者:Ya‐Nan Li、Fan Chen、Xing‐Guo Zhang、Hai‐Yong Tu
DOI:10.1002/adsc.202300777
日期:2023.11.21
An iodine-mediated radical cyclization of o-vinylaryl isocyanides with disulfides or diselenides was developed. The atom-economic reaction provides a method for regioselective construction of the 2-chalcogenated quinolines in 42–93% yields by incorporation of both chalcogen atoms of disulfides or diselenides into quinolines.
FeF3‐Promoted Radical Fluoroalkylation of o‐Alkenylaryl Isocyanides to Access 2‐Fluoroalkylated Quinolines
作者:Xin‐Yin Zhou、Wei‐Ming Zhang、Cheng‐Wei Lu、Hua‐Hua Wang、Xiao‐Hong Zhang、Xing‐Guo Zhang、Hai‐Yong Tu
DOI:10.1002/ejoc.202400434
日期:2024.8.12
fluoroalkylation was developed. In the presence of FeF3 and Cs2CO3, a variety of o-alkenylaryl isocyanides smoothly underwent the radical fluoroalkylation with perfluoroalkyliodides to afford biologically important 2-fluoroalkylated quinolines in 38–81 % yields. Moreover, the conditions are compatible with nonfluorinated alkyl iodides leading to 2-alkylated quinolines.
开发了一种通过铁(III)促进的自由基氟烷基化制备喹啉的有效方法。在 FeF 3和 Cs 2 CO 3存在下,多种邻烯基芳基异氰化物顺利地与全氟烷基碘化物进行自由基氟烷基化,以 38-81% 的产率提供具有生物学意义的重要的 2-氟烷基化喹啉。此外,该条件与产生2-烷基化喹啉的非氟化烷基碘相容。
De Novo Synthesis of 2,2′-Bipyridines and Related Bis-azines via Cascade Coupling and Double Pyridannulation of Isocyanides
Herein, we present a new and general protocol for the assembly of 2,2′-bipyridyls from nonpyridine substrates without using any metal catalysts or organometallic reagents. The process starts from the coupling of two 1,3-dienyl isocyanides followed by a 6π-electrocyclization/aromatization cascade featuring the simultaneous formation of two pyridinerings in a single operation. Notably, this strategy