O-乙基黄原酸甲酯合成工艺的研究

STUDY ON THE SYNTHETIC PROCESS OF O-ETHYL,S-METHYL DITHIOCARBONATE

从两方面对 O 乙基黄原酸甲酯的传统合成过程进行了改进 ,并认为碘甲烷实际上是用硫酸二甲酯直接合成黄原酸酯的过渡中间体。碘甲烷法的最佳反应条件为 :n ( CH3CH2 OH)∶ n ( CH3I) =1∶ ( 1 .1～ 1 .1 5 ) ,时间 75 min,收率 90 % ,纯度 99.7% ;利用含 I-废液回收碘甲烷的最佳反应条件为 :n[( CH3) 2 SO4]∶n( I- ) =1 .2∶ 1 ,时间 2 h,温度 5 5～ 60℃ ,碘甲烷回收率为 93.6% ,纯度为 99.3% ;硫酸二甲酯法的最佳反应条件为 :n( CH3CH2 OH)∶ n( ( CH3) 2 SO4)∶ n( CH3I) =1∶ 1 .2∶ 0 .0 5 ,时间 75 min,收率 87.5 % ,纯度99.1 %

The conventional synthetic process of Oethyl, Smethyl dithiocarbonate (EMDTC) with CH 3I was improved from two aspects, and the (CH 3) 2SO 4 method was presented as a new process. In which the iodomethane was considered as intermediate during the synthesis of dithiocarbonates. The optimal conditions were obtained as follows: as to the CH 3I mehtod, ① the yield of EMOTC achieved 90% at n(CH 3I)∶n(CH 3CH 2OH)=1∶(1.1～1.15), reaction time 75 minutes, refluxing, the purity was 99.7%; ② iodine ion containing waste liquor was treated with CH 3CH 2OH at n((CH 3) 2SO 4)∶n(I -)=1.2∶1, reaction time 2 hours, reaction temperature 55～60 ℃, the recovery of CH 3I was 98.6 %, the purity of CH 3I was 99.3%; as to the (CH 3) 2SO 4 method the yield of EMDTC achieved 87.5 % at n(CH 3CH 2OH)∶n ((CH 3) 2SO 4)∶n(CH 3I)=1∶1.2∶0.05, reaction time 75 min, refluxing, the purity of EMDTC was 99.1%.