碳酸二甲酯做甲基化试剂合成2,6-二氯苯甲醚

Synthesis of 2,6-Dichloroanisole with Dimethyl Carbonate as Methylating Agent

摘要:

采用碳酸二甲酯(DMC)代替传统的有毒有害试剂作为甲基化试剂，以2,6-二氯苯酚(DCP)为原料，在固体碱与相转移催化剂(PTC)的作用下，合成2,6-二氯苯甲醚(DCA)。考察了PTC种类及用量、物料配比、反应时间、反应温度和碱性催化剂用量对反应的影响。结果表明，最佳反应条件为：以聚乙二醇400（PEG-400）为PTC，x(PEG-400)=0.2%，n(DMC):n(DCP):n(K2CO3)=0.1:0.05:0.001，温度150 ℃，时间5 h，DCA的产率为87.3%，DCP的转化率为100%。优化条件下的重复实验表明，该反应易于控制，重复性好。

Abstract:

2,6-dichloroanisole(DCA) was prepared from 2,6-dichlorophenol(DCP) in the presence of potassium carbonate (K2CO3) and phase transfer catalyt(PTC), using dimethyl carbonate (DMC) as methylating reagent instead of conventional toxic reagents. The best yield(87.3%) of DCA and conversion (100%) of DCP were obtained under optimized conditions that polyethylene glycol 400 (PEG-400) was used as PTC, x(PEG-400)=0.2%, n(DMC):n(DCP):n(K2CO3)=0.1:0.05:0.001, the reaction temperature 150 oC, the reaction time 5 h. The repeat experiments showed that the technology possed a good repeatability under above optimum conditions.