Ultrasound-assisted synthesis of diversely functionalized tetrahydro-1H-Indole-4(5H)-one using BrOnsted base silica sodium carbonate (SSC) as a catalyst under solvent-free conditions

An ultrasound-promoted, environmentally benign, efficient procedure has been developed for the synthesis of biologically active tetrahydro-1H-indol-4(5H)-one using heterogeneous BrOnsted base silica sodium carbonate (SSC) as a catalyst under solvent-free conditions. In comparison to the conventional methods, this efficient green protocol provides remarkable advantages such as good to excellent yields, shorter reaction time, low cost, and easy workup procedure and bypasses the use of hazardous transition-metal catalysts and organic solvents. [GRAPHICS] .