磷钨酸催化合成2,6-萘二甲酸二甲酯

CATALYTIC SYNTHESIS OF DIMETHYL-2,6-NAPHTHALENE DICARBOXYLATE OVER PHOSPHOTUNGSTIC ACID

在 0 .2 L不锈钢高压釜中 ,用磷钨酸作催化剂 ,以 2 ,6萘二甲酸和甲醇为原料制备了 2 ,6萘二甲酸二甲酯。较优的反应条件为 :2 ,6萘二甲酸 0 .0 1 85 mol,甲醇∶ 2 ,6萘二甲酸 (物质的量比 ) =80∶ 1 ,反应温度1 80℃ ,反应时间 4～ 6h,催化剂用量为 2 ,6萘二甲酸质量的 1 %～ 3 %。酯收率大于 90 % ,产品不需重结晶 ,纯度大于 99.4%

In a 200 mL stainless steel autoclave, dimethyl 2,6 naphthalene dicarboxylate (DM 2,6 NDC) was prepared by reacting 2,6 naphthalenedicarboxylic acid (2,6 NDA) with methyl alcohol in the presence of phosphotungstic acid as catalyst. The optimum reaction conditions were determined as follows: the amount of (2,6 NDA) 0.018 5 mol, the molar ratio of methanol to 2,6 NDA 80∶1, reaction temperature 180 ℃, reaction time 46 h and the amount of catalysts 1%3% (based on the mass of 2,6 NDA). Under these conditions the yield of DM 2,6 NDC was >90% and the DM 2,6 NDC had a purity of at least 99.4% without recrystallization.