木质素磺酸催化4H-吡啶并[1,2-a]嘧啶-4-酮衍生物的合成  

Lignosulfonic acid-catalyzed synthesis of 4H-pyrido[1,2-a]pyrimidin-4-one derivatives

作　　者：毛渊渊 彭进松[1] 陈春霞[1] MAO Yuanyuan;PENG Jinsong;CHEN Chunxia(College of Chemistry,Chemical Engineering and Resource Utilization,Northeast Forestry University,Harbin 150040,Heilongjiang,China)

机构地区：[1]东北林业大学化学化工与资源利用学院,黑龙江哈尔滨150040

出　　处：《精细化工》2025年第1期128-134,共7页Fine Chemicals

基　　金：黑龙江省自然科学基金项目(LH2022B003)。

摘　　要：从造纸工业副产物木质素磺酸钠出发,通过离子交换法制备了木质素磺酸,并对其进行FTIR、酸碱滴定和凝胶渗透色谱表征。以木质素磺酸催化2-氨基吡啶与乙酰乙酸乙酯合成2-甲基-4H-吡啶并[1,2-a]嘧啶-4-酮为模板反应,考察了溶剂、温度、催化剂用量对反应的影响。得到优化反应条件为:2-氨基吡啶1.0 mmol、乙酰乙酸乙酯1.1 mmol、木质素磺酸0.09 g,在2 mL无水乙醇中于100℃下反应24 h。在该条件下改变底物上连接取代基团的种类和位置,合成了一系列4H-吡啶并[1,2-a]嘧啶-4-酮衍生物,产率为38%~84%,产物的结构经^(1)HNMR和^(13)CNMR表征。此外,对模板反应中催化剂的回收和再利用性进行了评价,在优化条件下催化剂使用4次,产率从81%降低到75%,扩大反应规模到克级,催化活性无显著变化。Lignosulfonic acid was prepared from ion exchange of sodium lignosulfonate,a by-product of paper industry,and characterized by FTIR,acid-base titration and gel permeation chromatography.Using the catalytic synthesis of 2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one from 2-aminopyridine with ethyl acetoacetate via lignosulfonic acid as a template reaction,the influence of solvent,temperature and catalyst amount on the reaction was analyzed.The optimized reaction conditions were obtained as follows:1.0 mmol of 2-aminopyridine,1.1 mmol of ethyl acetoacetate,0.09 g of lignosulfonic acid,and reacted in 2 mL of ethanol absolute at 100℃for 24 h.Under the optimized reaction conditions,a series of 4H-pyrido[1,2-a]pyrimidin-4-ones in yields of 38%~84%were obtained by changing the type and position of the binding substituent groups on the substrate,with the structures confirmed by ^(1)HNMR and ^(13)CNMR.Data from evaluation on the recovery and reuse of the catalyst showed that,under the optimized conditions,the yield was reduced from 81%to 75%when the catalyst was recycled for 4 times,and the reaction scale was successfully expanded to gram level without significant change in catalytic activity.

关 键 词：木质素磺酸 环化反应 4H-吡啶并[1 2-a]嘧啶-4-酮 含氮双杂环 绿色合成 催化技术 

分 类 号：TQ426[化学工程]