1846-78-2Relevant articles and documents
Isomerisation of 2-Aryl-4-oxo-2,3-dihydrobenzopyranopyrimidines to 2-Aryl-4-hydroxy-5H-benzopyranopyrimidines
O'Callaghan, Conor N.
, p. 1335 - 1337 (2007/10/02)
The base-catalysed condensation of 3-carbamoyl-2-iminochromen with aromatyc aldehydes yields 2-aryl-4-oxo-2,3-dihydrobenzopyranopyrimidines, which isomerise to stable 2-aryl-4-hydroxy-5H-benzopyranopyrimidines.The synthesis of 3-oxo-2H-benzopyranopyrazole is also described.