Al(NO3)3 · 9H2O: An Efficient Catalyst for the One-Pot Synthesis of 3,4-Dihydropyrimidin-2(1H)-ones Both under Reflux or Solvent-Free Conditions

Al(NO3)3 · 9H2O efficiently catalyzes the three-component Biginelli reaction between an aldehyde, a β-dicarbonyl compound, and urea or thiourea in refluxing ethanol and solvent-free (SF) conditions to afford the corresponding dihydropyrimidinones in high yields. The advantages of this method involve the easy procedure, the environmentally friendly process, and the low cost of the Lewis acid catalyst

Easy Access to Coumarin Derivatives Using Alumina Sulfuric Acid as an Efficient and Reusable Catalyst under Solvent-Free Conditions

A new and efficient condition for the use of alumina sulfuric acid (ASA) as a heterogeneous catalyst in the Pechmann condensation reaction in solvent-free condition for the formation of coumarins has been reported