Sulfonated mesoporous silica as efficient reusable heterogeneous catalyst for one-pot synthesis of novel poly-functionalized spirothiazolidin-4-ones: A green strategy

Abstract

Herein, we have developed a simple and highly efficient protocol for the one-pot synthesis of poly-functionalized spirothiazolidine-4-ones using the sulfonated mesoporous silica (MCM-SO₃H) as effectual heterogenous acid catalyst. In comparison to the reported synthetic methods for the synthesis of 4-thiazolidineone and spirothiazolidine-4-one derivatives, this strategy showed a high product yields were obtained and prevention of using toxic or explosive solvents are established. Using of MCM-SO₃H as an efficient acid catalyst for synthesis spirothiazolidin-4-one derivatives under mild and environmentally friendly conditions are the most important aspect of this study. The interesting features of this protocol are the environmentally benign conditions, simplicity of reaction, short reaction times, excellent yields, easily work-up and a catalyst reusability. All synthesized compounds are new and confirmed by ¹H and ¹³C NMR spectral data.