Abstract A general and efficient room-temperature procedure is developed for high-yield synthesis of 2H-benzo[b][1,4]thiazin-3(4H)-onederivatives in one pot from the reaction of 2-aminothiophenols with 2-bromoalkanoates in ionicliquid [bmim]NO3 without the use of any catalyst, base, or additive. Products were obtained in good yields by simple extraction with Et2O followed by evaporation of the volatile
A solvent-free procedure was developed for the reaction of 2-aminothiophenols with 2-bromoalkanoates, where KF-Al2O3 support and ball milling cooperatively lead to a green and efficient synthesis of several benzothiazinone derivatives in good to excellent yields. The catalyst could be recycled in further reactions while maintaining its activity. (C) 2015 Elsevier Ltd. All rights reserved.