1578-70-7Relevant articles and documents
Green synthesis method of fluorinated chiral compound
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Paragraph 0032; 0033; 0034; 0035; 0036-0038; 0096-0098, (2017/07/23)
The invention discloses a green synthesis method of a fluorinated chiral compound shown in a formula (1). The green synthesis method comprises the following steps: by taking a 1,3-dicarbonyl compound shown in a formula (2) and a fluorinated reagent N-fluorinated benzene sulfonamide shown in a formula (3) as raw materials, under the action of a chiral catalyst, performing ball milling reaction under a solvent-free condition and performing thin-plate chromatography tracking reaction till complete reaction to obtain a reaction mixture; post-processing the reaction mixture to obtain the fluorinated chiral compound shown in the formula (1). The green synthesis method disclosed by the invention is less in solvent pollution, high in reaction speed, high in yield, good in asymmetric selectivity, wide in reaction substrate range and easy for reaction reagent obtaining, and has important application values; the prepared compound can be taken as an important organic intermediate to be applied to the fields of medicines, pesticides and the like.
Synthesis, Properties, and Reactivity of N,N'-Difluorobipyridinium and Related Salts and Their Applications as Reactive and Easy-To-Handle Electrophilic Fluorinating Agents with High Effective Fluorine Content
Umemoto, Teruo,Nagayoshi, Masayuki,Adachi, Kenji,Tomizawa, Ginjiro
, p. 3379 - 3385 (2007/10/03)
N,N′-Difluoro-2,2′-, -2,4′-, -3,3′-, -4,4′-bipyridinium and substituted N,N′-difluoro-2,2′-bipyridinmm bis(triflates), bis(tetrafluoroborates), bis(hexafluorophosphates), and bis(hexafluoroantimonates) 1-9 were synthesized in high yields by the direct fluorination of a mixture of a bipyridyl and a Lewis acid, a Br?nsted acid, or the alkali metal salt of an acid. The higher homologues, trimer 10 and polymer 11, were also synthesized. Unsubstituted or electron-donating group-substituted N,N′- difluorobipyridinium salts are stable nonhygroscopic crystals, while the electron-withdrawing group- substituted N,N′-diflurobipyridinium salts 3, 5, and 6 are moisture-sensitive crystals. Hydrolysis of 1b in boiling water gave 3,3′-dihydroxy-2,2′-bipyridyl. The reactivity determination indicated that the fluorinating capability decreased in the order 2,2′- ? 2,4' > 3,3′- ≈ 4,4′-isomer ? N-fluoropyridinium salt and that the two N-F moieties in a molecule were effective for fluorination. This fluorination occurred in a step-by-step manner, and the reactivity difference between the first and second fluorinations was very small. N,N′-Difluoro-2,2′-bipyridinium bis(tetrafluoroborate) (1b) is thus shown to be a highly reactive and easy-to-handle electrophilic fluorinating agent with the high effective fluorine content (103.3 g/kg) for preparing many fluoro organic compounds.
Direct Fluorination of 1,3-Dicarbonyl Compounds
Chambers, Richard D.,Greenhall, Martin P.,Hutchinson, John
, p. 21 - 22 (2007/10/02)
1,3-Dicarbonyls, such as 1,3-diketones and 1,3-ketoesters, react directly with elemental fluorine at room temperature to give the corresponding 2-fluoro- and, in some cases, 2,2-difluoro-compounds in high yield.
