ionic liquids 1-n-buty1-3-methylimmidazolium tetrafluoroborate(BF4),l-n-buty1-3methylimmidazolium bromid(Br)and l-n-buty1-3-methylimmidazoliumhexafluorophosphate(PF6)were adopted as the microwave absorbent.Under the radiation of the microwave,the condensation reaction between benzaldehyde and barbituric acid was promoted,the yields wasmuch higher than the same reaction without ionic liquids.the catalytic activity of different ionic liquid,and the reaction time and the power of the microwave to the reaction was studied.As the microwaveabsorbent,BF4could well promote the condensation reaction between other aromatic aldehydes and barbituric acid as well.The structures of the product,5-alkylene barbituric acid,and its derivation were testified through by 1HNMR.
