Quinolines from arylamines

Quinolines from arylamines and a,fi-unsaturated carbonyl compounds... 

Quinolines from ortho-Acyl-Arylamines and Carbonyl Compounds ortfto-Acyl-arylamines react with ketones having an a-methylene to give quinolines. 

Quinoline synthesis. 2,4-Disubstituted quinolines are synthesized in one operation from arylamines, aldehydes, and 1-alkynes. A mixture of AuCh and CuBr is used to promote the condensation. The effectiveness of AuCh to transform A-propargylarylamines to quinolines at room temperature has been independently verified. ... 

Quinolines. Quinolines are obtained by following the procedure of an indole synthesis from arylamines by changing the reaction partners to 3-aminopropanol. Yields are moderate (11 examples, 29-46%). 

W. Wei, J. Wen, D. Yang, X. Sun, J. You, Y. Suo, H. Wang, Tetrahedron 2013, 69, 10747-10751. Iron-catalyzed three-component tandem process a novel and convenient synthetic route to quinoline-2,4-dicarboxylates from arylamines, gly-oxylic esters and a-ketoesters. 

Early studies from Torii reported a three-component reaction based, as mentioned above, on the conjugate addition of dialkylamines to alkynones [91]. Here the highly reactive Michael acceptor 96 is generated in situ from a carbonylative coupling between 2-aminophenylacetylenes and aryliodides. Addition of dialkylamines to 96 produces enaminoketones 97, which then undergo a cyclocondensation between the carbonyl group and the internal arylamine, affording substituted quinolines 98 (Scheme 8.41). 

Dichloromethine cyanine 17 which can be obtained in high yield from phosgeniminium chloride (PI) and N,N-dimethylacetamide has proven to be a particularly versatile source of push-pull ynamines. Arylamines, however cyclise on the aryl group and 2,4-bis(dimethylamino)quinolines are the final products80). The intermediary ynamines can only be detected by the IR. The process is catalysed by traces of hydrogen chloride see also (5.3). 

In an analogous manner, benzo(f)quinolines (22P) and benzo(h)quinolines (231), starting from (3-naphthylamine and a-naphthylamine via the corresponding vinamidines (225f-h) and (225 k-l), have been synthesized (Method A) or, much more simply, in a one-pot process, by boiling a mixture of equivalent amounts of arylamine, vinamidinium salt (7), and sodium methoxide in pyridine (Method B). 

The isomerization of an arylamine to an N-containing aromatic heterocyclic compound would, in principle, open a new route from aromatic hydrocarbons, via nitroaromatic compounds and arylamines, to pyridines and quinolines. We were therefore interested to discover the potential of this reaction, and have studied its scope, optimum conditions, and its mechanism [8-11]. 

Moreover, a new multicomponent domino reaction leading to 2-aryl-4-amino-quinolines and [l,8]naphthyridmes starting from carbon monoxide, 2-ediy-nyl-arylamines, aryliodides, and primary amines was recently reported [45]. The palladium-mediated process (Scheme 13.17, cycle A) involves a triple-domino sequence, for example, carbonylative coupling and inter- and intramolecular... 

In 2005, Yi and coworkers reported a catalytic C-H bond activation and cyclization protocol by using the catalyst Ru3(CO)j 2/NH4PFg. This catalytic system offers an efficient method for the synthesis of tricyclic quinoline derivatives from regioselective coupling of benzocyclic amines with 2 equiv. of alkynes (Eq. (7.21)) [27]. Later, the catalytic coupling reactions of acyclic arylamines with terminal... 

Evidence has been produced " which suggests that cycloprop[f>]indoles and other products from the photolysis of ethyl 2-cyano-l,2-dihydroquinoline-l-carboxylates, e.g. (110), arise not, as was assumed previously, via an aza-hexatriene intermediate but via the excited singlet state of (110) or a dipolar species of form (111). In contrast, the long-assumed (but recently doubted) intermediacy of 1,2-dihydroquinolines in the Doebner-von Miller quinoline synthesis has been confirmed. The isolable dihydroquinolines are produced in high yield on allowing the arylamine and acetaldehyde to stand at room temperature for 24 hours. 

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