Recyclable Boron Sulfonic Acid as an Environmentally Benign Catalyst for the One-Pot Synthesis of Coumarin Derivatives under Solvent-Free Condition

Rezayati, S.; Sajjadifar, S.

Recyclable Boron Sulfonic Acid as an Environmentally Benign Catalyst for the One-Pot Synthesis of Coumarin Derivatives under Solvent-Free Condition

Document Type : Original Research Articles

Authors

S. Rezayati

S. Sajjadifar

Department of Chemistry, Payame Noor University, PO BOX 19395-4697 Tehran, Islamic Republic of Iran

Abstract

A mild and green method has been developed for the preparation of coumarins derivatives through the one-pot reactions. In our study,various phenols and ethyl acetoacetate compound in which we used silica-supported boron sulfonic acid [SiO2/B(SO4H)3] as a new, highly efficient and tri-functional inorganic Brønsted acid catalyst were processed under solvent-free condition and thermal. The catalysts were separated easily from reaction mixture, regenerated after a simple activation step and reused at least six times without signiﬁcant loss in catalytic activity. The most significant features of this procedure are:short period of conversion and excellent yields, simple experimental procedure, environmentally benign, the elimination of corrosive liquid acids and green aspects by avoiding toxic conventional catalysts and solvents.

Keywords

Silica boron sulfonic acid

Heterogeneous catalysts

Pechmanncondensation

Solvent-free

Brønsted acid and Lewis acid catalyst