分子筛辅助合成马来海松酸三甲酯

Synthesis of Trimethyl Maleopimaric Acid Assisted by Molecular Sieve

使用3A分子筛作为脱水剂,在压力釜中合成了马来海松酸三甲酯。最佳工艺条件为:马来海松酸酐4 g(0.01 mol)、3A分子筛5.4 g、甲醇11.6 g(0.36 mol)和ZnO 0.02 g,加入反应釜,250℃反应4 h。在该条件下,马来海松酸三甲酯的收率为98%,酸值18.5 mg/g,酯化度为2.85。对产物进行了红外光谱表征和核磁共振分析,13C NMR和红外光谱分析表明产物的结构和目标合成物结构一致。根据1H NMR计算得到,产物中马来海松酸三甲酯的纯度为84%。分子筛的加入能够明显降低产物的酸值。

Trimethyl maleopimaric acid was synthesized in an autoclave using 3A molecular sieve as a dehydrating agent.The optimum technological conditions are as follows： maleopimaric anhydride 4 g（0.01 mol）,3A molecular sieve 5.4 g,methanol 11.6 g（0.36 mol） and ZnO 0.02 g were added into an autoclave,and temperature was hold at 250℃ for 4 h.Under these condition,the yield of trimethyl maleopimaric acid was 98 %,acid value was 18.5 mg/g and esterification degree of product was 2.85.FT-IR and NMR were utilized to determine the structure of the product.It was confirmed that the structure of the product was the same as target product.According to 1 H NMR data the purity of trimethyl maleopimaric acid was 84%.The acid value of the product can be reduced dramatically by adding molecular sieve.