Solvent-Free Synthesis of Thiobarbituric Acids Using Amberlyst-15 as a Green Catalyst

Background: Solvent-free reaction for the synthesis of thiobarbituric acids (TBAs) by the reaction of 1,3-disubstituted thioureas and malonyl chloride using Amberlyst-15 as a green catalyst has been reported. Recyclability of the catalyst was possible up to five runs without loss of catalytic activity. Conclusion: The simple workup, isolation without column, excellent yields, is main advantages of present protocol.