135590-91-9Relevant articles and documents
Preparation method of mefenpyr-diethyl
-
, (2020/09/09)
The invention relates to a preparation method of mefenpyr-diethyl, which specifically comprises the following steps: (a) mixing ethyl 2-chloroacetoacetate, 2,4-dichloroaniline, inorganic acid and water, and then adding a sodium nitrite aqueous solution to form a reaction system, and performing diazotization and substitution reactions, so as to obtain ethyl 2-chloro-2-(2,4-dichlorobenzene diazo) acetoacetate; and (b) adding an inorganic base into the reaction system to adjust the pH value to 5-7, then adding a bicarbonate aqueous solution to carry out a hydrolysis reaction to obtain ethyl 2-chloro-2-(2,4-dichlorobenzylidenehydrazino)acetate, then sequentially adding a polymerization inhibitor, ethyl methacrylate and the bicarbonate aqueous solution to carry out cyclization, and carrying outpost-treatment to obtain the mefenpyr-diethyl. Compared with the prior art, the intermediate generated through diazotization and substitution is stable, the intermediate does not need to be separated, the method is easy and convenient to operate, reaction conditions are mild, sodium bicarbonate (or potassium bicarbonate) is used for hydrolysis, the raw material price is low, and the dosage is small.
NOVEL FORM OF MEFENPYR-DIETHYL,PROCESS FOR PREPARATION AND USE THEREOF
-
Page/Page column 11, (2017/06/27)
A crystalline form of mefenpyr-diethyl of formula (I), the crystal preparation process, the analyses of the crystal through various analytical methods and using the crystal to prepare stable agrochemical formulation are provided. The use of various solvents towards the crystalline form preparation conditions is also provided.
Pyrazolines for protecting crop plants against herbicides
-
, (2008/06/13)
Compounds of the formula (I) STR1 where X, n, R1, R2 and R3 are as defined in claim 1 are suitable as antidotes against phytotoxic secondary effects of herbicides in crop plants without adversely affecting the action of the herbicides against harmful plants.