Synthesis of uniquely substituted 4H-Chromeno[2,3-d] pyrimidin-2-one derivatives by l-Proline catalyzed green chemistry method

This paper describes synthesis of novel 4H-Chromeno[2,3-d] pyrimidin-2-one compounds by green chemistry method using l-proline as the catalyst. Firstly, a one-pot reaction of resorcinol, malononitrile, and benzaldehyde with proline in water at room temperature on reaction gave 2-amino-7-hydroxy-4-phenyl-4H-1-benzopyran-3-carbonitrile and in next step (2-amino-7-hydroxy-4-phenyl-4H-1-benzopyran-3-carbonitrile was alkylated in the presence of K₂CO₃ in dry acetone at 70–80 °C to give substituted benzopyran 3-carbonitriles. The amino and carbonitrile parts in the substrate were converted into different novel substituted chromeno derivatives on cyclization with urea. The presence of a pyrimidine ring makes this moiety highly biologically efficient.