The reaction for synthesis of substituted coumarins in solvent-free condition at room temperature.

Entry	Reactant	Catalyst	Temperature (°C)	Time (min)	%Yield
1	Resorcinol + ethylacetoacetate	ZrO2–TiO2	RT	180	97
2	Resorcinol + ethylacetoacetate	ZrO2–ZnO	RT	240	63
3	Resorcinol + ethylacetoacetate	ZrO2/cellulose	RT	180	Nil
4	Catechol + ethylacetoacetate	ZrO2–TiO2	80	240	55
5	o-Nitrophenol + ethylacetoacetate	ZrO2–TiO2	80	240	Nil
6	Resorcinol + ethylacetoacetate	Without catalyst	80	240	Nil