Silver-Catalyzed Domino Hydroarylation/Cycloisomerization Reactions of 2-Alkynylquinoline-3-carbaldehydes: Access to (Hetero)arylpyranoquinolines

Abstract

A silver trifluoromethanesulfonate catalyzed efficient access to the indolylpyranoquinoline scaffold is reported. Starting from 2alkynylquinoline-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)arylfunctionalized 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.

Recent advances in the chemistry of 2-chloroquinoline-3-carbaldehyde and related analogs

“…Sonogashira coupling reaction of alkyne derivatives with quinolones 16 in anhydrous DMF or THF containing trimethylamine in the presence of [PdCl 2 (PPh 3 ) 2 ] and CuI as catalysts yielded the desired 2-alkynyl-3-formyl-quinolines 29a-r (Scheme 7). 63…”

An Overview of Ag‐catalyzed Synthesis of Six‐membered Heterocycles

“…Belmont and co‐workers could describe a facile and efficient methodology towards the synthesis of indolylpyranoquinoline 115 derivatives [65] . The reaction proceeded with 2‐alknylquinoline‐3‐carbaldehydes 93 with substitution on the alkynyl and quinoline parts and a nucleophile 114 , in the presence of 10 mol % silver trifluoromethanesulfonate in 1,2‐dichloroethane (Scheme 65).…”