1027513-97-8Relevant articles and documents
Controlling the cleavage of carbon-carbon bonds to generate α,α-difluorobenzyl carbanions for the construction of difluoromethylbenzenes
Khatri, Hari R.,Han, Changho,Luong, Erica,Pan, Xiaoliang,Adam, Amna T.,Alshammari, Maali D.,Shao, Yihan,Colby, David A.
, p. 11665 - 11675 (2019)
Controlling the cleavage of carbon-carbon bonds during a chemical reaction is a substantial challenge; however, synthetic methods that accomplish this objective produce valuable and often unexplored reactivity. We have designed a mild process to generate α,α-difluorobenzyl carbanions in the presence of potassium carbonate by exploiting the cleavage of C-C bonds during the release of trifluoroacetate. The initiating reagent is potassium carbonate, which represents an improvement over existing protocols that require a strong base. Fragmentation studies across substituted arenes and heteroarenes were conducted along with computational analyses to elucidate reactivity trends. Furthermore, the mildly generated α,α-difluorobenzyl carbanions from electron-deficient aromatics and heteroaromatic rings can react with aldehydes to create derivatives of difluoromethylbenzenes, which are valuable synthetic targets.
Synthetic method of aromatic ring group or aromatic heterocyclic tetrazole
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Paragraph 0055-0063, (2020/12/30)
The synthetic method comprises the following steps: (1) reacting 1.0 eq of ArI or HArI with 1.2 eq of ethyl 2, 2-difluoroacetate in the presence of DMSO as a solvent and 4.0 eq of Cu under the protection of nitrogen at 30 DEG C and 50 DEG C, and purifying to obtain a first intermediate compound; (2) dissolving 1.0 eq of the first intermediate compound in a mixed solvent of THF and water, adding 2.0 eq of LiOH, reacting at room temperature for 2 hours, spin-drying the solvent, adding HCl until the pH value is equal to 3, and filtering to obtain a second intermediate compound; and (3) reacting 1.0 eq of the second intermediate compound with 2.0 eq of diphenyl azide phosphate in the presence of 2.5 eq of triethylamine by taking tert-butyl alcohol as a solvent to generate aromatic ring group or aromatic heterocyclic tetrazole. The invention provides a novel synthetic method of aromatic ring group or aromatic heterocyclic tetrazole, wherein a target compound can be more conveniently obtained, and reagents participating in the reaction are low in toxicity, mild in reaction condition, simple and safe in aftertreatment, good in product quality and suitable for large-scale production.
Silver-Mediated 18F-Labeling of Aryl-CF3 and Aryl-CHF2 with 18F-Fluoride
Verhoog, Stefan,Pfeifer, Lukas,Khotavivattana, Tanatorn,Calderwood, Samuel,Collier, Thomas Lee,Wheelhouse, Katherine,Tredwell, Matthew,Gouverneur, Véronique
supporting information, p. 25 - 28 (2015/12/26)
We report the synthesis of [18F]arylCF3 and [18F]arylCHF2 derivatives from arylCF2Br and arylCHFCl precursors applying a silver-mediated halogen exchange with [18F]fluoride. In the absence of Ag(I)OTf, no reaction takes place at room temperature for both classes of substrates; this result demonstrates the beneficial role of silver(I) as a means to induce 18F-incorporation under very mild conditions.
