一二三四区视频,亚洲少妇熟女色,日本久热无码视频网,欧美国产日韩大尺度,亚洲a视频,久久少妇一区二区,日韩999无码视频,刺激久久久久久久,啊啊啊啊不要啊在线

Welcome to chemicalbook!
Chinese English Japanese Germany Korea
010-86108875
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List Methimazole
60-56-0

Methimazole synthesis

5synthesis methods
Methimazole, 1-methyl-2-imidazolthiol (25.2.5), is synthesized by reacting aminoacetic aldehyde diethylacetal with methylisothiocyanate and subsequent hydrolysis of the acetal group of the resulting disubstituted urea derivative 25.2.4 by a solution of sulfuric acid, during which a simultaneous cyclization reaction takes place, forming the imidazole ring of the desired methimazole .

-

Yield:60-56-0 150 kg

Reaction Conditions:

with hydrogenchloride in water at 20 - 30;Large scale;

Steps:

1.c

in 5 of adding the reactor 410 kg methylamino acetaldehyde diethyl acetal, 270 kg of potassium thiocyanate and 500 kg of purified water, stirring the mixture at room temperature after completely dissolved, to the 5 of the pre-prepared reaction in the cauldron adds by drops 1mol/L dilute hydrochloric acid 1000 kg, control of the temperature of the reaction solution in the 30 °C left and right.After the reaction, the reaction liquid water is removed by reduced pressure distillation, the resulting solid with ethyl acetate is dissolved again, after the undissolved substances, ethyl acetate is removed by reduced pressure distillation. The resulting solid is dissolved in purified water, adjust the pH to 1, the cooling crystallization to obtain the purity is greater than 99% of the product, vacuum drying to obtain 2-mercapto-1-methyl imidazole final product 150 kg, yield of 47.2%.

References:

CN103214421,2016,B Location in patent:Paragraph 0024; 0025

Methimazole Related Search:

巴塘县| 金山区| 万州区| 藁城市| 泽州县| 汕头市| 绥宁县| 靖边县| 桐城市| 苍南县| 奉化市| 沂水县| 温州市| 深水埗区| 镇沅| 黑龙江省| 东丽区| 磐石市| 南宁市| 株洲市| 澳门| 竹山县| 北辰区| 琼海市| 攀枝花市| 宁河县| 开封市| 玉林市| 石首市| 拜泉县| 区。| 内丘县| 西盟| 靖远县| 广平县| 平山县| 兴仁县| 专栏| 桂阳县| 达拉特旗| 息烽县|