Author/Authors :
Quiroga، نويسنده , , Jairo and Portilla، نويسنده , , Jaime and Abonيa، نويسنده , , Rodrigo and Insuasty، نويسنده , , Braulio and Nogueras، نويسنده , , Manuel and Cobo، نويسنده , , Justo، نويسنده ,
Abstract :
A series of 6-(2-hydroxybenzoyl)-5-methyl-7-phenylpyrazolo[1,5-a]pyrimidines 5 have been synthesized directly by the solvent-free reaction between 5-amino-1H-pyrazoles 1 and 3-benzoyl-2-methyl-4H-chromen-4-one 4. This solvent-free reaction proceeds in a regiospecific fashion by intramolecular opening of the γ-pyrone ring in a Michael-type reaction, that followed by cyclization via nucleophilic attack of endocyclic pyrazole nitrogen toward benzoyl group gives the pyrazolo[1,5-a]pyrimidines 5. The use of this method affords high yields in short reaction times.
