Highly efficient synthesis of polysubstituted 1,2-dihydroquinolines via tandem reaction of α-ketoesters and arylamines catalyzed by fluorous hydrazine-1,2-bis(carbothioate) and NCS

A simple and convenient tandem reaction of α-ketoesters with primary or secondary aromatic amines for the synthesis of polysubstituted 1,2-dihydroquinolines has been developed. The catalytic system (fluorous hydrazine-1,2-bis(carbothioate)/NCS) of the reaction has the advantages of operational simplicity, high efficiency, as well as easy recyclability.