One-Pot Synthesis of Coumarin Derivatives

Abstract

With 2,3,4-trimethoxybenzaldehyde (1) as raw material, through the methoxy redn. reaction, Knoevenagel condensation reaction, amino redn. reaction and acetylation reaction three new 3-amide-substituted 7,8-dimethoxy coumarin derivs. were synthesized. Their structure was confirmed by 1H NMR, 13C NMR and IR anal. The effect of reaction conditions on the yield of reaction intermediate (2) was studied. The optimum conditions were found as follows: n1:nAlCl3 = 1:1, toluene 90 mL, reaction temp. 80 ± 2°C and reaction time 4 h. [on SciFinder(R)]