以CO_(2)为羧基源温和高效制水杨酸类化合物  

Mild and efficient preparation of salicylic acid compounds with CO_(2) as carboxyl source

作　　者：郑修畅 李国玲[1] 赵云[1] 倪中海[1] 陆诗建 陆超 ZHENG Xiuchang;LI Guoling;ZHAO Yun;NI Zhonghai;LU Shijian;LU Chao(School of Chemical Engineering,China University of Mining and Technology,Xuzhou 221116,Jiangsu,China;Institute of Carbon Neutrality,China University of Mining and Technology,Xuzhou 221116,Jiangsu,China;China Power Huachuang Electric Power Technology Research Co.,Ltd.,Shanghai 200086,China)

机构地区：[1]中国矿业大学化工学院,江苏徐州221116 [2]中国矿业大学碳中和研究院,江苏徐州221116 [3]中电华创电力技术研究有限公司,上海200086

出　　处：《低碳化学与化工》2025年第2期53-60,共8页Low-Carbon Chemistry and Chemical Engineering

基　　金：江苏省碳达峰碳中和科技创新专项(BE2023852);中国矿业大学安全学科群自主创新项目(2022ZZX03)。

摘　　要：水杨酸类化合物是一种广泛用于医药、香料、染料、农药和橡胶助剂等精细化学品的重要原料。然而基于Kolbe-Schmitt反应,由CO_(2)作为羧基源制备水杨酸类化合物时存在温度高、压力高、反应时间长和收率低等问题。提出了一种通过CO_(2)羧化苯酚或4-取代基苯酚合成水杨酸类化合物的新方法。以KOH为脱质子碱,二甲苯为溶剂,Cs_(2)CO_(3)、K_(2)CO_(3)和2,4,6-三甲基苯酚钾盐(TMPK)为共催化剂,高效羧化苯酚和4-取代基苯酚制备水杨酸类化合物,并表征了各羧化产物的理化性质。系统考察了催化剂用量、CO_(2)压力、温度、助催化剂用量、反应时间和反应底物等对苯酚和4-取代基苯酚羧化反应的影响,提出了碳酸盐与TMPK共催化合成水杨酸和5-取代基水杨酸可能的反应机理。结果显示,Cs_(2)CO_(3)+TMPK的催化剂组合有效优化了反应条件,实现了温和条件(温度为120℃、CO_(2)压力为0.5 MPa、n(Cs_(2)CO_(3)):n(TMPK):n(原料)为1:1:1和反应时间为4 h)下CO_(2)高效羧化苯酚(单程收率为60%)和4-取代基苯酚(单程收率为60%~90%)制备水杨酸类化合物。以该法合成的羧化产物邻位选择性高达100%。Salicylic acid compounds are an important raw material widely used in fine chemicals such as medicine,spices,dyes,pesticides and rubber additives,etc.However,based on the Kolbe-Schmitt reaction,the preparation of salicylic acid compounds with CO_(2)as a carboxyl source has some problems,such as high temperature,high pressure,long reaction time and low yield.A new method for the synthesis of salicylic acid compounds by CO_(2)carboxylation phenol and 4-substituted phenol was presented,which uses KOH as deprotonation base,xylene as solvent,Cs_(2)CO_(3),K_(2)CO_(3)and 2,4,6-trimethylphenol potassium salt(TMPK)as cocatalysts to achieve CO_(2)efficient carboxylation phenol and 4-substituted phenol.The physicochemical properties of each carboxylation product were characterized.The effects of catalyst dosage,CO_(2)pressure,temperature,cocatalyst dosage,reaction time and reaction substrate on the carboxylation reaction of phenol and 4-substituted phenol were systematically investigated.The possible reaction mechanism of the synthesis of salicylic acid and 5-substituted salicylic acid cocatalyzed by carbonate and TMPK was proposed.The results show that the catalyst combination of Cs_(2)CO_(3)+TMPK effectively optimizes the reaction conditions.Under mild conditions,the preparation of salicylic acid compounds by efficient CO_(2)carboxylation phenol(one-way yield of 60%)and 4-substituted phenol(one-way yield of 60%~90%)was realized.The ortho-selectivity of carboxylation products synthesized by this method is as high as 100%.

关 键 词：Kolbe-Schmitt反应 CO_(2) Cs_(2)CO_(3) 2 4 6-三甲基苯酚 5-取代基水杨酸 羧化 

分 类 号：TQ245.4[化学工程—有机化工]