- Synthesis method of thiodicarb
-
The invention provides a synthesis method of thiodicarb, and the method comprises the following steps: synthesizing a ligand, and synthesizing thiodicarb. According to the invention, trialkyl tertiaryamine is used as a catalyst for synthesis of thiodicarb, and during synthesis of thiodicarb, the reaction pressure is increased, and the industrial synthesis reaction time is shortened to 5 hours; inthe thiodicarb synthesis process, the temperature is controlled in three stages, the reaction temperature is controlled at 10-15 DEG C for 1-1.5 hours, the reaction temperature is controlled at 20-25DEG C for 1-1.5 hours, the reaction temperature is controlled at 30-35 DEG C for 1-2 hours, and gradient heating is adopted, so the defect of multiple side reactions caused by always reacting at a relatively high temperature is avoided.
- -
-
Paragraph 0020-0062
(2021/03/13)
-
- Synthesis method of thiodicarb
-
The invention discloses a synthesis method of thiodicarb, which comprises the following steps: (1) dividing a solvent into two parts, dissolving methomyl in one of the two parts to obtain a methomyl solution, and dissolving 18-crown ether-6 in the other part of the mixture to obtain a solution of the 18-crown-6; and (2) under a closed condition, dropwise adding a part of sulfur dichloride into the 18-crown-6 solution, after dropwise adding is completed, dropwise adding the residual sulfur dichloride to react with the methomyl solution, and after dropwise adding is completed, continuing to carry out heat preservation reaction to obtain the thiodicarb. The method is high in reaction selectivity, by-products are reduced, the obtained product is high in purity and yield, and meanwhile, the problem that a pipeline is easily blocked in the production process can be effectively solved. The method is simple in process operation and suitable for large-scale industrial production.
- -
-
Paragraph 0031-0059
(2021/05/12)
-
- Preparation method of thiodicarb
-
The invention discloses a preparation method of thiodicarb. The preparation method comprises the following steps: (1) dividing a solvent into two portions, dissolving methomyl in one of the two portions to obtain a methomyl solution, and dissolving 4-dimethylaminopyridine in the other portion to obtain a solvent which contains a catalyst; and (2) dividing sulfur dichloride into two portions, dropwise adding one portion of the sulfur dichloride in the solvent which contains the catalyst under a closed condition, meanwhile, dropwise adding the other portion of sulfur dichloride and carrying outdropwise adding reaction on the other portion of sulfur dichloride and the methomyl solution obtained in step (1), and carrying out insulating reaction after dropwise adding is finished to obtain thethiodicarb. The preparation method of the thiodicarb has the advantages that the reaction selectivity is high, the purity of the obtained product is high, the content of thiodicarb isomer is smaller than 0.4%, the yield is high and the like.
- -
-
Paragraph 0004; 0025; 0026
(2018/06/28)
-