An efficient, convenient, and eco-friendly biocatalytic approach was developed for the synthesis of quinoline derivatives via the α-chymotrypsin-catalyzed Friedländer reaction. Interestingly, α-chymotrypsin exhibited higher catalytic activity in an ionic liquid (IL) aqueous solution as compared to that observed in our previous relevant study, which was conducted using an organic solvent, and a series of substrates gave similar excellent yields at lower reaction temperature and under reduced enzyme-loading conditions.
Keywords: Friedländer reaction; biocatalysis; ionic liquid; promiscuity; quinolines; α-chymotrypsin.