A green, environmentally benign, facile and efficient one-pot three-component reaction of benzaldehyde, barbituric acid and meldrum's
acid for the synthesis of 5-phenyl-5,6-dihydro-1H-pyrano[2,3-d]pyrimidine-2,4,7(3H)-trione derivatives using cerric ammonium nitrate
(CAN) as a catalyst in aqueous medium under ultrasonic irradiation is described. 1,3-dimethyl barbituric acid gives slightly lower yield as
compared to barbituric acid and takes longer time to complete the reaction. Excellent yields, no need of base, and simple workup procedure
are the prominent features of this protocol.
Key words: Pyrano[2,3-d]pyrimidine, 1,3-dimethyl barbituric acid, ceric ammonium nitrate (CAN), ultrasound irradiation
|