One-Pot Synthesis of Dihydropyrimidinones by Dodecylphosphonic Acid as Solid Bronsted Acid Catalyst under Solvent-Free Conditions via Biginelli Condensation

Dodecylphosphonic acid is a solid Bronsted acid that catalyzes efficiently the preparation of dihydropyrimidinones by Biginelli condensation under solvent-free conditions. This protocol offers several advantages including high yields, short reaction times, easy work-up, and use of cheap, relatively moderate acidic and safe catalyst.