4-Tert-butylcatechol (4-TBC) is synthesized from catechol and MTBE using sulfuric acid catalyst. The methods of analysis and characterization on reaction process are investigated. 13 C NMR technique combined with gas chromatography (GC is introduced to characterize the synthesized products. Adopting 13C NMR technique to analyze the progress of reactions real timely, optimum process parameters can be obtained. The results show that characterizing the product by GC alone is much complex, and it is difficult to distinguish the peaks of impurities. By 13C NMR method,the chemical shift of various carbon positions in the molecular structure can be determined,thus the reaction mechanism and carbon positions for reactions could be inferred,in a word,the components in product can be distinguished more clearly. Under the conditions of a mass ratio of catechol to MTBE of l,a catalyst dosage of 6% (based on catechol) ,a reaction temperature of (120 + 2) ℃ ,MTBE adding time of 2. 0-2. 5 h,at 1. 5 h after the completion of adding MTBE,the content of 4-TBC in the mixed product is 84. 3% ,and a 1. 6% of 3,5-DTBC is detected.%以邻苯二酚和甲基叔丁基醚为原料、浓硫酸为催化剂合成对叔丁基邻苯二酚(4-TBC).采用13C NMR与气相色谱结合的方法分析表征4-TBC合成产物,采用13C NMR方法实时监测4-TBC的反应过程,并对反应工艺条件进行考察.结果表明,单纯采用气相色谱方法分析表征产物时,过程复杂且对杂峰无法判定,而采用13C NMR方法可以确定分子结构中不同碳位的化学位移、推测反应碳位与机理,并能更清晰判定产物中组分的组成.在邻苯二酚与MTBE物质的量比为1.1、硫酸用量为邻苯二酚质量的6％、反应温度为(120±2)℃、MTBE滴加时间为2.0～2.5 h的条件下,MTBE滴加完成后1.5h时反应混合物中4-TBC质量分数为84.3％,3,5-DTBC质量分数为1.6％.
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