1421925-29-2Relevant academic research and scientific papers
Silver-Catalyzed Domino Hydroarylation/Cycloisomerization Reactions of 2-Alkynylquinoline-3-carbaldehydes: Access to (Hetero)arylpyranoquinolines
Bontemps, Alexis,Mariaule, Ga?lle,Desbène-Finck, Stéphanie,Helissey, Philippe,Giorgi-Renault, Sylviane,Michelet, Véronique,Belmont, Philippe
, p. 2178 - 2190 (2016)
A silver trifluoromethanesulfonate catalyzed efficient access to the indolylpyranoquinoline scaffold is reported. Starting from 2-alkynylquinoline-3-carbaldehyde units with various substitution patterns on the quinoline and alkynyl parts, the use of silver trifluoromethanesulfonate (10 mol%) in 1,2-dichloroethane allowed a domino hydroarylation/cycloisomerization reaction, generating (hetero)aryl-functionalized pyranoquinolines. The heteroarenes that were used are N-methylindole (18 compounds, 67-100%), indole, and 2-methylindole (4 compounds, 36-89%), and the reaction was also compatible to a lesser extent with arenes such as pyrroles (5 compounds, 43-90%), 1,3,5-trimethoxybenzene, and 3-methylbenzofuran.
FeCl3·6H2O-catalyzed facile and efficient synthesis of pyrano[4,3-b]quinolines and isochromenes
Asthana, Mrityunjaya,Singh, Jay Bahadur,Singh, Radhey M.
, p. 615 - 618 (2016/01/20)
An inexpensive 1 mol % FeCl3·6H2O reagent has been developed for the synthesis of 1,3-disubstituted 1H-pyrano[4,3-b]quinolines from o-arylethnylquinonylmethanol via 6-endo-dig cyclization of alcoholic -OH onto alkynes in good to excellent yields. The reaction conditions were successfully exploited on primary and tertiary alcohol analogs. The reagent was further generalized with the aromatic alcohol analogs providing the synthesis of isochromenes in good yields. The enhancement in the reaction rates and yields from primary to secondary to tertiary alcohols could be attributed to inductive effect of alkyl groups which enhanced the nucleophilicity of hydroxyl group and accelerated the cyclization mode.
An economical nucleophilic route toward facile synthesis of pyrano[4,3-b]quinolin-1-ones via 6-endo-dig cyclization of o-alkynylquinoline esters
Sharma, Neha,Asthana, Mrityunjaya,Nandini, Durgesh,Singh,Singh, Radhey M.
, p. 1822 - 1829 (2013/04/10)
Metal-free facile synthesis of pyrano[4,3-b]quinoline-1-ones is described from methyl 2-arylethynylquinoline-3-carboxylates via intramolecular cyclization in excellent yields. The cyclization reactions are facilitated using cheap and easily available KOH base in MeOH. The reaction conditions did not require dry solvent, inert atmosphere, and avoid further column chromatography purification of the products. These compounds could be further used as building blocks for the synthesis of 2H-benzo[b][1,6]naphthyridin-1-one and 1-chloro-benzo[b][1,6] naphthyridines.
