Potassium-Exchanged Zirconium Hydrogen Phosphate [α-Zr(KPO4)2]-Catalyzed Synthesis of 2-Amino-4H-pyran Derivatives under Solvent-Free Conditions

A high-yielding, one-pot, three-component synthesis of functionalized 2-amino-4 H -pyrans from β-dicarbonyl compounds, activated cyanomethylene compounds, and aldehydes, mediated by potassium-exchanged zirconium hydrogen phosphate [α-Zr(KPO 4 ) 2 ], is reported. The protocol shows excellent versatility, as it can be applied to aromatic, aliphatic, or α,β-unsaturated aldehydes under solvent-free conditions.