In this work, Boehmite nanoparticles (BNPs) were synthesized in water using commercially available materials and further N,N,N′,N′-tetraethyldiethylentriamin (TEDETA) was supported on the surface of BNPs, and used as organo-basic catalyst in four-component Hantzsch reaction that provides access to pharmaceutically polyhydroquinoline derivatives and Knoevenagel reaction to afford α,β-unsaturated compounds. All products were obtained in excellent yields (89–98%) and good reaction times under green condition such as water and ethanol solvents. This catalyst was characterized using FT-IR, SEM, EDS, and TGA techniques. This catalyst was reused for several times without the signifcant loss of their catalytic efciency. In addition, stability of catalyst after recycling was confrmed by TGA, SEM, EDS and FT-IR techniques.