Synthesis of 4‐(Iso)Quinolinyl‐3(2H)‐furanones from (Iso)Quinoline N‐oxides and 1,4‐Diyn‐3‐ones: A Comparison of Copper Catalysis and Metal‐free Reaction

Abstract

A facile synthesis of (iso)quinolinyl-3(2H)-furanones from (iso)quinoline N-oxides and 1,4-diyn-3-ones in the presence of copper catalyst or under metal-free conditions was developed. The resulting (iso)quinolinyl-3(2H)-furanones could be easily converted to (iso)quinolinyl-isoxazoles, pyrazoles and polycyclic (iso)quinoline derivatives. In addition, the success in one-pot, metal-free synthesis of isoquinolinyl-3(2H)-furanone starts from isoquinoline shows the capacity of this method for the metal-free derivatization of pyridine, quinoline and isoquinoline.

Tandem Hydroamination/Cyclization Access to N-2(5H)-Furanone Derivatives for COX-2 Inhibitor

“…Amazingly, the expected continuous Sonogashira coupling reaction and acetylene hydroamination would happen as anticipated . Based on this proposition, an improving method was devoted to fusing polycyclic heterocycles catalyzed by copper . And thus, compound 1a was synthesized via a tandem reaction of ( S )-3-bromo-5-methoxy-4-(phenylamino)­furan-2­(5 H )-one 2 and phenylacetylene 3 (Scheme c).…”

Synthesis of 3(2H)‐Furanones: A Review

“…A metal-free and a Cu-catalysed syntheses of (iso)quinolinyl 3(2H)-furanones 487 were developed by Wang and co-workers in 2019 (Scheme 101). [91] Under copper catalysis both electrondonating and electron-withdrawing substituents on the 1,4-…”

Recent Advances in the Synthesis of C2‐Functionalized Pyridines and Quinolines Using N‐Oxide Chemistry

“…Interestingly, the synthesis of 413 through the reaction of (iso)quinoline N ‐oxides with 1,4‐diyn‐3‐ones 412 can proceed with or without copper catalysis (Scheme 117). [152] However, the copper catalyst promotes the final cyclization in 415 by activation of the carbon–carbon triple bond, providing better yields under milder conditions.…”