cas 50594-66-6, Acifluorfen | Articles data

Articles about 50594-66-6Total 10 be found

Article title
Article abstract
Author
Journal number and time
Download

Method for nitration synthesis of acifluorfen in microreactor
The invention relates to a method for nitration synthesis of acifluorfen in a microreactor. The method for nitration synthesis of acifluorfen in the microreactor comprises the following steps: proportionally pumping a nitrating agent composed of a solution containing raw materials 3 (2chlorine 4trifluoromethyl phenoxy) benzoic acid, fuming sulfuric acid and fuming nitric acid into the micro-channel reactor in parallel through a metering pump; and reacting to synthesize the 5 (2chlorine 4trifluoromethyl phenoxy) 2nitrobenzoic acid (acifluorfen). The acifluorfen is synthesized by nitration of the micro-channel reactor, the phase contact area is increased, and the mass transfer rate and the reaction rate are high; The heat transfer efficiency is increased, reaction heat is transferred quickly, and safety is improved; The continuous operation is achieved, product quality is stable, operation is flexible, and amplification is easy; under optimized conditions, the reaction conversion rate can reach 99.19%, and the reaction selectivity is 81.08%.
-
Paragraph 0021-0036

(2021/02/13)

Preparation process of acifluorfen
The invention relates to the technical field of herbicides, and discloses a preparation process of acifluorfen, which comprises the following steps: synthesizing 3-[2-chloro-4-(trifluoromethyl) phenoxy] benzoic acid by using 3, 4-dichlorobenzotrifluoride as a raw material, and carrying out nitration reaction by using concentrated sulfuric acid and concentrated nitric acid as mixed acids to obtainacifluorfen. According to the production process disclosed by the invention, an extracted 3-[2-chloro-4-(trifluoromethyl) phenoxy] benzoic acid solution is directly conveyed to a nitration kettle fornitration reaction, the process is simpler, the production progress can be effectively accelerated, the yield can be effectively increased, the nitration reaction temperature in the process is about 40 DEG C, the reaction time is shorter, the problem of more impurities caused by high temperature and overlong reaction time can be avoided, meanwhile, the time cost can also be saved, and the preparation process has the characteristics of mild reaction conditions and high yield.
-
Paragraph 0026; 0030-0032; 0035-0037; 0040-0041

(2020/10/14)

Preparation method of fomesafenbulk drug intermediate acifluorfen
The invention provides a preparation method of fomesafenbulk drug intermediate acifluorfen, and belongs to the technical field of pesticides. According to the method, a low-temperature nitrification mode is adopted,nitrylions can be slowly released, so that the reaction tends to be gentle, the selective competitiveness of a target product is enhanced, polynitrification and ectopic nitrification byproducts are inhibited, and the content of the intermediate acifluorfen is effectively increased. The method provided by the invention can be effectively applied to production and application of the fomesafen technical.
-
Paragraph 0028-0047

(2020/09/12)

Preparation method of acifluorfen
The invention relates to the field of herbicides and specifically discloses a preparation method of acifluorfen. The acifluorfen is a compound shown by formula (1) in the specification. The method comprises the following steps: (1) dropwise adding the compound shown by formula (2) in the specification into an organic solvent containing alkali carbonate and the compound shown by formula (3) in the specification so that the compound shown by formula (3) contacts and reacts with the compound shown by formula (2) to obtain the compound shown by formula (4); and (2) performing alkaline hydrolysis and acidification of the compound shown by formula (4) to obtain the compound shown by formula (1). By adopting the preparation method, the target compound can be prepared with relatively high yield in relatively mild reaction conditions.
-
(2016/10/27)

METHOD FOR THE NITRATION OF SUBSTITUTED BENZENES IN THE PRESENCE OF PROPIONIC ACID
The aim of the invention is to provide a widely applicable method for the nitration of substituted benzenes.
-
Page/Page column 2

(2011/01/11)

Chemical process
A process for the purification of a compound of general formula I: wherein: R1is hydrogen or C1-C6alkyl, C2-C6alkenyl or C2-C6alkynyl (any of which may optionally be substituted with one or more substituents selected from halogen and OH) or COOR4, COR6, CONR4R5or CONHSO2R4; R4and R5are each independently hydrogen or C1-C4alkyl optionally substituted with one or more halogen atoms; R6is a halogen atom or a group R4; R2is hydrogen or halo; R3is C1-C4alkyl, C2-C4alkenyl or C2-C4alkynyl, any of which may optionally be substituted with one or more halogen atoms, or halo; or, where appropriate, a salt thereof; from a mixture containing the compound of general formula I together with one or more isomers or di-nitrated analogues thereof; the process comprising dissolving the mixture in a suitable crystallisation solvent and recrystallising the product from the resulting crystallisation solution; characterised in that the crystallisation solution contains not more than 25% loading of the compound of general formula I wherein loading is defined as:weight[!it!]?[!it!]of[!it!]?[!it!]pure[!it!]?[!it!]compound[!it!]?[!it!]of[!it!]?[!it!]formula[!it!]?[!it!]I×100weight[!it!]?[!it!]of[!it!]?[!it!]pure[!it!]?[!it!]compound[!it!]?[!it!]of[!it!]?[!it!]formula[!it!]?[!it!]I+weight[!it!]?[!it!]of[!it!]?[!it!]solvent and in that the temperature to which the solution is cooled for crystallisation is not greater than about 30° C.
-
Example 6

(2008/06/13)

Process for the nitration of diphenylethers
A process for the preparation of a compound of general formula I: wherein: R1 is hydrogen or C1-C6 alkyl, C2-C6 alkenyl or C2-C6 alkynyl, any of which may optionally be substituted with one or more substituents selected from halogen and OH; or COOR4, COR6, CONR4R5 or CONHSO2R4; R4 and R5 are each independently hydrogen or C1-C4 alkyl optionally substituted with one or more halogen atoms; R6 is a halogen atom or a group R4; R2 is hydrogen or halo; R3 is C1-C4 alkyl, C2-C4 alkenyl or C2-C4 alkynyl, any of which may optionally be substituted with one or more halogen atoms; or halo; the process comprising reacting a compound of general formula II: wherein R1, R2 and R3 are as defined for general formula I; with a nitrating agent comprising nitric acid or a mixture of nitric and sulphuric acids in the presence of an organic solvent and in the presence of acetic anhydride, characterized in that the molar ratio of acetic anhydride to compound of general formula II is from about 1:1 to 3:1.
-
(2008/06/13)

Substituted diphenyl ether herbicides and process for use
This invention relates to substituted diphenyl ethers having selective herbicidal properties and having the formula: STR1 wherein R is a saturated or unsaturated, straight chain or branched aliphatic hydrocarbon radical of from 1 to 18 carbon atoms wherein one or more of the --CH2 -- groups can be replaced with --O--, --S--, --S--S--, --SO--, --SO2 -- or --NR2 -- and said hydrocarbon radical is optionally substituted with halogen, trihalomethyl, cyano, aryl, hydroxy, alkoxy, nitro or cycloalkyl having 3 to 6 carbon atoms; R1 is STR2 R3 is STR3 R2 is hydrogen or a saturated or unsaturated straight or branched chain aliphatic radical having from 1 to 8 carbon atoms, optionally substituted with halogen, hydroxy, alkoxy, cyano or nitro; R4 and R5 are independently a saturated or unsaturated, straight or branched chain aliphatic radical having 1 to 8 carbon atoms optionally substituted with halogen, trihalomethyl, alkoxy or cyano; hydrogen or phenyl optionally substituted with halogen, alkyl, alkoxy, trihalomethyl, nitro or cyano; R6 is a saturated or unsaturated straight chain or branched aliphatic radical containing from 1 to 8 carbon atoms, optionally substituted with halogen, trihalomethyl, cyano, hydroxy, nitro, acetoxy, alkoxy, thioalkoxy or aryl; an aryl radical optionally substituted with halogen, trihalomethyl, hydroxy, cyano, nitro, alkyl or alkoxy; a cyclic 3-6 membered ring alkylene or 5-6 membered ring alkenylene or benzyl optionally substituted with halogen, trihalomethyl, alkyl, hydroxy, alkoxy or cyano; R7 is an alkylene diradical having from 1 to 6 carbon atoms; X and X' are each independently --O--, --S-- or --NR2 -- L, M and N are each independently hydrogen, hydroxy, halogen, trihalomethyl, nitro, cyano, alkyl or alkoxy having from 1 to 4 carbon atoms and STR4 m has a value of from 1 to 6 and n in each instance has a value of from 0 to 1.
-
(2008/06/13)

Preparation of 5-(2-halo-4-trifluoromethylphenoxy)-2-nitrobenzoic acid and salts and esters and amides
A process for preparing a substantially pure, isomer free 5-(2-halo-4-trifluoromethylphenoxy)-2-nitrobenzoic acid or its esters, salts and amides by the basic condensation of a 4-trifluoromethylphenol and a 1-chloro-3-substituted-4-nitrobenzene followed by halogenation. All known previous routes afforded, in addition to the desired product, a number of inactive isomers.
-
(2008/06/13)

Process for preparing phenoxybenzoic acids
Phenoxybenzoic acids and esters of the formula STR1 wherein R is hydrogen or alkyl and X is hydrogen or chlorine can be prepared by reacting the disalt of 3-hydroxybenzoic acid with a 3-chloro-4-halobenzotrifluoride. These phenoxybenzoic acids and esters can then be selectively nitrated to give the corresponding 2-nitro-5-(substituted)phenoxybenzoic acids and esters. The nitrated esters can also be prepared by first nitrating the corresponding acid and then esterifying with an appropriate alcohol.
-
(2008/06/13)