Copper‐Catalyzed Tandem Reaction of Enamino Esters with ortho‐Halogenated Aromatic Carbonyls: One‐Pot Approach to Functionalized Quinolines

Abstract

An efficient and practical approach for the synthesis of functionalized quinolines has been developed by using the copper‐catalyzed tandem C–C bond formation and C–N coupling reaction of enamino esters and ortho‐halogenated aromatic carbonyl compounds. Various functional groups were tolerated under the reaction conditions, and a series of quinolines were easily obtained in moderate to good yields. A gram‐scale reaction was also performed to demonstrate a further application of this synthetic method.

Electrochemically Induced Synthesis of Sulfonylated N-Unsubstituted Enamines from Vinyl Azides and Sulfonyl Hydrazides

“…As a result of radical transformations of vinyl azides, various products can be synthesized: ketones, imines, and unsubstituted enamines. , Among all possible products, selective synthesis of functionalized N -unsubstituted enamines is a quite challenging task , due to a limited substrate scope or need for tedious and hydrolysis-sensitive operations . Development of an efficient method for N -unsubstituted enamines synthesis will allow them to become accessible as synthetic intermediates on the way to various nitrogen-containing heterocycles − and chiral amines. , …”

Recent advances in the tandem copper-catalyzed Ullmann–GoldbergN-arylation–cyclization strategies

“…They focused on enamino esters as one of the starting materials to access functionalized quinolines, which complements the previous work. 48 2.4.4. Synthesis of substituted 4-quinolones.…”

The synthesis ofN‐containing heterocyclic compounds catalyzed by copper/L‐proline

“…In 2018, Chen’s group designed CuI/ L ‐proline‐catalyzed tandem C‐C condensation and C‐N coupling reaction of enamino esters 91 and ortho ‐halogen aromatic carbonyls 92 to synthesize quinolines 93 (Scheme 17). [ 51 ] The method utilized inexpensive enamino esters and ortho ‐halogen aromatic carbonyls as the starting materials to provide quinolines in moderate to good yields. When only CuI was used as the catalyst, the yield of product 93a dropped from 86% to 67%.…”