An efficient and expeditious synthesis of 1,2,4-triazolidine-3-thiones using meglumine as a reusable catalyst in water

A simple, convenient, and eco-friendly procedure has been developed using meglumine (15 mol%) as a green catalyst for the synthesis of 1,2,4-triazolidine-3-thiones under one-pot condition. Variously substituted aldehydes or ketones reacted well with thiosemicarbazide to give desired compounds in extremely good quantity. The developed protocol offers several advantages such as shorter reaction times, mild reaction conditions, easy workup, simple purification procedures, water as a solvent, and wide substrate scope tolerance. Further, the catalyst was recycled (up to 4 cycles) without compromising the yield of the final products.

Automated summary

A simple and eco-friendly procedure using meglumine as a green catalyst has been developed to synthesize 1,2,4-triazolidine-3-thiones under one-pot condition. The reaction exhibits excellent efficiency with various aldehydes or ketones and thiosemicarbazide, offering advantages such as shorter reaction times, mild reaction conditions, easy workup, simple purification procedures, water as a solvent, and wide substrate scope tolerance. Additionally, the catalyst can be recycled up to 4 cycles without compromising the yield of the final products.