Synthesis of Naphthopyranopyrimidines Using Formic Acid as an Effective Catalyst under Solvent-free Conditions

An environmentally friendly, one-pot, three-component synthesis of 8,10-dimethyl-12-aryl-12H-naphtho[1′,2′:5,6]pyrano[2,3-d]pyrimidine-9,11-diones was achieved via coupling aromatic of aldehydes, β-naphthol and 6-amino-1,3-dimethyl uracil in the presence of formic acid as a catalyst under solvent-free conditions at 90 °C. This method has several advantages, such as efficiency, good yield, short reaction time, cleaner reaction profiles, ease of product isolation, operational simplicity and inexpensive, effective and catalyst.