Novel approaches for the synthesis of a library of fluorescent chromenopyrimidine derivatives.

A library of some new fluorescent chromenopyrimidine derivatives has been synthesized by new approaches. Water-promoted and one-pot reaction can produce new dialkylylamino)-5H-chromeno[2,3-d]pyrimidin-2-yl) phenols. These compounds can also be produced using domino reaction. Two parallel methods are compared. Novel N-alkyl-N-phenyl-5H-chromeno[2,3-d]-pyrimidin-4-amines and 4-alkoxy-5H-chromeno[2, 3-d]pyrimidines are synthesized by Lewis-acid catalyzed reactions. The fluorescence emission intensity of the four compounds from each of libraries after excitation in 290 nm is measured. Compound 2-(4,5-bis(N-methyl-N-phenylamino)-5H-chromeno[2,3-d]pyrimidin-2-yl)phenol was isolated as a byproduct. The details of an interesting exchangeable intramolecular H- bonding of two of the new compounds are reported by X-ray analysis data.