Aims: Synthesis of dihydropyrimidinones derivatives.
Background: carrying out reactions in the green route and organic solvent-free conditions.
Objective: Regioselective Michael addition of dihydropyrimidinones to acrylic esters.
Methods: The reaction proceeded in the presence of K2CO3/TBAB, a media of inorganic base K2CO3 and organic ionic salt TBAB (tetrabutylammonium bromide) at 100°C.
Results: A series of new dihydropyrimidinone derivatives using aza-Michael addition reaction were synthesized under solvent-free conditions.
Conclusion: The reaction is characterized by high efficiency, relatively short reaction time, high yields, simple environmentally friendly reaction conditions.
Other: The reaction of acrylic esters with dihydropyrimidinones produced N3-substituted derivative of dihydropyrimidinones with 85-95% yields in 6 h.
Keywords: Regioselective synthesis, dihydropyrimidinones, aza-Michael addition, acrylic esters, solvent conditions, organic salts.