Efficient and environmentally-benign three-component synthesis of quinolines and bis-quinolines catalyzed by recyclable potassium dodecatungstocobaltate trihydrate under microwave irradiation.

Microwave-assisted one-pot three-component reaction between aromatic amines, aromatic aldehydes and phenylacetylene is accomplished efficiently in the presence of catalytic amounts of potassium dodecatungstocobaltate trihydrate (K5CoW12O40·3H2O) to afford the corresponding quinolines and bis-quinolines in excellent yields. Selective conversion of aromatic aldehyde and also arylacetylene to their corresponding quinolines in the presence of aliphatic aldehyde and alkylacetylene, respectively, can be considered as noteworthy advantages of this method and makes it a useful and attractive process for the synthesis of quinoline derivatives. The catalyst could be reused for several cycles without any significant loss of its catalytic activity