摘要
以浓硫酸改性活性炭[H2SO4/AC(Cat)]为催化剂,在无溶剂条件下,取代酚和乙酰乙酸甲酯(2)经Pechmann缩合反应合成了5个香豆素衍生物,其结构经1H NMR,13C NMR和IR确证。以间甲酚(1a)和2合成4,7-二甲基香豆素(3a)为例,考察原料配比[r=n(1a)∶n(2)]、反应温度、Cat用量及反应时间对Pechmann反应的影响。在最佳反应条件[1a 5 mmol,r=1.0∶2.0,Cat 18%,于120℃反应3 h]下,3a收率80%。
Five coumarin derivatives were synthesized by Pechmann condensation of substituted phenol and methyl acetoacetate （2） using active carbon （AC） supported concentrated sulfuric acid [H2SO4/AC（Cat）] as the catalyst under solvent-free conditions.The structures were confirmed by 1H NMR,13C NMR and IR.The effects of raw material ratio,reaction temperature,reaction time and Cat dosage on Pechmann condensation were investigated by reaction of metacresyl（1a） with 2.The results showed that the optimum reaction conditions at 120 ℃ for 3 h were as follows：1a 5 mmol,r =n（1a） ∶n（2） =1.0∶2.0,Cat dosage was 18%,the yield of 3a was 80%.
出处
《合成化学》
CAS
CSCD
北大核心
2014年第3期408-411,共4页
Chinese Journal of Synthetic Chemistry
