1583-59-1Relevant articles and documents
Fluorodesulfurization of Thionobenzodioxoles with Silver(I) Fluoride
Newton, Josiah J.,Brooke, Alan J.,Duhamel, Bastian,Pulfer, Jason M.,Britton, Robert,Friesen, Chadron M.
, p. 13298 - 13305 (2020)
Difluorobenzodioxole is an important functional group found in both pharmaceuticals and agrochemicals. The late-stage introduction of this functional group is challenged by typical fluorination conditions of HF and strong oxidants. Here, we demonstrate that a range of difluorobenzodioxoles can be prepared from catechols in two steps through conversion into thionobenzodioxoles, followed by desulfurative fluorination with silver(I) fluoride. These mild reaction conditions are compatible with a variety of functional groups and enable access to a range of functionalized difluorobenzodioxoles.
PROCESS FOR THE PREPARATION OF 2,2-DIFLUORO-1,3-BENZODIOXOLE AND INTERMEDIATES THEREOF
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Page/Page column 7, (2020/05/15)
The present invention relates to a process for preparing 2,2-difluoro-1,3-benzodioxole. The process comprises a step of reacting 1,3-benzodioxole with chlorine in benzotrifluoride in the present of a radical initiator. The present invention also relates to the process for preparing 2,2-dichloro-1,3-benzodioxole which is used as an intermediate in preparation of 2,2-difluoro-1,3-benzodioxole.
Preparation method of difluoropiperidine
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Paragraph 0020-0039; 0044-0047, (2018/09/08)
The invention relates to a preparation method of a drug intermediate, and particularly provides a preparation method of difluoropiperidine. The preparation method includes: adopting a microchannel reactor, and continuously and uniformly pumping a difluoropiperidine solution into a module A for pre-cooling; continuously and uniformly pumping fluorine mixed gas into a module B for pre-cooling; allowing mixing reaction sequentially in modules C, D, E and F, controlling reaction temperature at minus 40 DEG C-20 DEG C, and collecting a product after retaining for 5s-10min; subjecting the product towater washing, rectification, separation and purification to obtain difluoropiperidine. Difluoropiperidine prepared by the method has the advantages of high atom economy, quick reaction, low cost, little pollution, environment friendliness and safety.
One-pot preparation method of 2,2-difluoro-1,3-benzodioxole
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Paragraph 0008; 0011, (2017/08/30)
The invention relates to a one-pot preparation method of 2,2-difluoro-1,3-benzodioxole. The one-pot preparation method of 2,2-difluoro-1,3-benzodioxole is characterized by comprising the following steps: adding piperonyl cyclonene, phosphorus oxychloride and phosphorus pentachloride in a lined polytetrafluoroethylene stainless steel bottle, rising temperature to reflux, ending the reaction when the content of piperonyl cyclonene taken as a raw material is detected to be less than 0.2% by GC, carrying out vacuum rectification on a reaction solution to distill off phosphorus trichloride which is a byproduct and phosphorus oxychloride taken as a solvent; cooling to the temperature of 0 to 5 DEG C after the vacuum rectification is finished, dropwise adding hydrogen fluoride liquid at the vacuum degree of minus 0.1 to minus 0.09MPa, then carrying out heat preservation and releasing the byproduct, namely hydrogen chloride; then dropwise adding a saturated sodium carbonate aqueous solution, adjusting the PH value of the solution to be 6.5 to 7.5, stirring and standing to be stratified, taking an organic layer and distilling to obtain a finished product, namely 2,2-difluoro-1,3-benzodioxole which is colorless and transparent liquid. The one-pot preparation method of 2,2-difluoro-1,3-benzodioxole disclosed by the invention has the advantages of low reaction temperature, high safety and improved yield.
4 - (2,2-difluoro -1,3-Benzodioxole-4-yl) pyrrole-3-nitrile synthetic method
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Paragraph 0045; 0055-0056; 0067; 0074; 0086-0087, (2018/07/10)
The invention discloses a synthetic method of 4-(2,2-difluoro-1,3-benzodioxole-4-yl)pyrrole-3-nitrile. The method comprises the following steps of: preparing an intermediate 2,2-difluorobenz-1,3-dioxole through reacting catechol with dibromodifluoromethane, and preparing an intermediate 2-cyano-3-(2,2-difluorobenz-1,3-dioxole-4-yl)-2-acrylate. The fludioxonil prepared by the synthetic method provided by the invention has the purity of more than 99.0% and the total yield of more than 45.0%; the synthetic method has the advantages of cheap and easily available raw materials, simple process, high product yield in each step, good purity, low production cost, applicability to batch industrial production and the like.
Selective aliphatic fluorination by halogen exchange in mild conditions
Saint-Jalmes, Laurent
, p. 85 - 90 (2007/10/03)
HF-Base media, in particular (HF)10-pyridine or (HF) 3-triethylamine, allow aliphatic chlorine-fluorine exchanges on acid-sensitive molecules. Depending on the nature (pyridine or triethylamine), stoichiometry of the base and temperature, selective mono-, di-, or tri-chlorine-fluorine exchanges on trichloromethyl groups alpha to sulfur, oxygen and carbon atoms can be obtained.
Process for fluorurating ethers
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Page 4, (2008/06/13)
The invention relates to a new process of fluorination of aromatic ethers in the alpha position on the side chain, passing through the corresponding chlorinated derivative without isolation thereof, in a dichloro-benzotrifluoride as solvent.
Process for the α-chlorination of aryl ethers
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, (2008/06/13)
Aryl ethers are chlorinated in the α-position by a process in which they are metered into a reaction vessel at the same time as chlorine, the reaction being carried out at temperatures in the range from 60° to 150° C.
Benzoheterocyclyl ketone hydrazone insecticides
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, (2008/06/13)
Benzoheterocyclyl ketone hydrazones of the formula STR1 in which Y is methylene, difluoromethylene or oxygen and n is 0 or 1, compositions thereof and their use as insecticides are disclosed and exemplified.
