Introduction of titania sulfonic acid (TiO₂-SO₃H) as a new, efficient, and reusable heterogenous solid acid catalyst for the synthesis of biscoumarins

GRAPHICAL ABSTRACT

Abstract

Titania sulfonic acid (TiO₂-SO₃H) is easily prepared by the reaction of TiO₂ with neat chlorosulfonic acid and characterized using a variety of techniques, including infrared, x-ray diffraction, Brunauer-Emmett-Teller, scanning electron microphotographs, pH analysis, and Hammett acidity function. This reagent can be used as an efficient and reusable solid acid catalyst for the promotion of the synthesis of biscoumarin derivatives in water. All reactions are performed under completely heterogeneous reaction conditions in excellent yields during acceptable reaction times.

Keywords:

• TiO₂
• titania sulfonic acid (TSA)
• solid acid
• biscoumarins
• reusable catalyst