Abstract
A green, rapid, and efficient methodology is developed for the synthesis of
1-phenyl-3,5-pyrazolidinedione (3) by the reaction of malonic acid with phenyl
hydrazine in the presence of phosphorous oxychloride under solvent-free conditions.
The later compound 3 was used as a versatile precursor for green synthesis
of chalcone derivatives (4a-h) and spiroheterocyclic compounds (5a-h)
with good to excellent isolated yields. The chemical structures of the synthesized
compounds were elucidated on the basis of elemental and spectral
analyses.