99687-75-9Relevant academic research and scientific papers
Impact of the Difluoromethylene Group in the Organocatalyzed Acylative Kinetic Resolution of α,α-Difluorohydrins
Andrei, Daniela,Bressy, Cyril,Desrues, Titouan,Médebielle, Maurice,Merad, Jérémy,Parrain, Jean-Luc,Pons, Jean-Marc,Quintard, Adrien
supporting information, p. 24924 - 24929 (2021/10/19)
Due to the omnipresence of chiral organofluorine compounds in pharmaceutical, agrochemical, and material chemistry, the development of enantioselective methods for their preparation is highly desirable. In the present study, the enantioselective organocatalyzed acylation of α,α-difluorohydrins using a commercially available chiral isothiourea is reported through a kinetic resolution (KR) process. It reveals that the difluoromethylene moiety (C(sp3)F2) can serve as a directing group through electrostatic fluorine–cation interactions, greatly improving the enantioselectivity of the KR. In this context, a broad range of fluorinated alcohols such as valuable 4,4-difluoro-1,3-diols could be synthesized with exquisite enantiocontrol (typically >99:1 er). Turning to 2,2-difluoro-1,3-diols, we also demonstrated that aromatic and fluorinated groups were mutually compatible to provide the expected enantioenriched adducts with >99:1 er.
Method for synthesizing alpha-fluorinated ketone through hydrazone aliphatic chain monoketone
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Paragraph 0062-0064; 0099-0101; 0123-0125, (2021/02/06)
The invention belongs to the technical field of organic synthesis, and provides a method for synthesizing alpha-ketone fluoride through hydrazone aliphatic chain monoketone, which comprises the following steps of: reacting aliphatic chain monoketone with hydrazine hydrate to obtain hydrazone, and reacting hydrazone with a compound represented by formula 2 under a heating condition to complete hydrazone defluorination. The fluorinated product is widely applied to medicines, the reaction conditions are mild, and the process is simple.
Mild and selective α-fluorination of carbonyl compounds (ketones, 1,3-diketones, β-ketoesters, α-nitroketones, and β-ketonitriles) with Selectfluor (F-TEDA-BF4) in imidazolium ILs [BMIM/PF6 or BMIM/NTf2] with Br?nsted-acidic IL [PMIM(SO3H)/OTf] as promoter
Reddy, A. Srinivas,Laali, Kenneth K.
supporting information, p. 5495 - 5499 (2015/09/21)
Structurally diverse ketones, 1,3-diketones, and β-ketoesters, were selectively monofluorinated with Selectfluor (F-TEDA-BF4) (1 equiv) in [BMIM][PF6] as solvent and [PMIM(SO3H)][OTf] as promoter under mild conditions. In selected cases, the monofluorinated products were transformed to the gem-difluoro derivatives by employing an additional equivalent of Selectfluor, and gem-difluoro-derivatives were synthesized directly from the substrates by employing 2 equiv of Selectfluor. The method was extended to monofluorination of representative α-nitroketones and β-ketonitriles using [BMIM][NTf2] without the need for promoters. The described method offers the added advantage of recycling and reuse of the IL solvent. (Chemical Equation Presented).
Ir-catalysed formation of C-F bonds. From allylic alcohols to α-fluoroketones
Ahlsten, Nanna,Martin-Matute, Belen
supporting information; experimental part, p. 8331 - 8333 (2011/09/12)
A novel iridium-catalysed tandem isomerisation/C-F bond formation from allylic alcohols and Selectfluor to prepare α-fluorinated ketones as single constitutional isomers is reported.
A facile synthesis of α-fluoro ketones catalyzed by [Cp*IrCl2]2
Ahlsten, Nanna,Bartoszewicz, Agnieszka,Agrawal, Santosh,Martin-Matute, Belen
supporting information; experimental part, p. 2600 - 2608 (2011/10/02)
Allylic alcohols are isomerized into enolates (enols) by [Cp*IrCl2]2. The enolates react with Selectfluor present in the reaction media. This method produces α-fluoro ketones as single constitutional isomers in high yields. Georg Thieme Verlag Stuttgart. New York.
Micellar-system-mediated direct fluorination of ketones in water
Stavber, Gaj,Zupan, Marko,Stavber, Stojan
scheme or table, p. 589 - 594 (2009/07/09)
A micellar system was developed and applied for direct regioselective fluorination of a variety of cyclic and acyclic ketones to α-fluoroketones in water as reaction medium with Selectfluor F-TEDA-BF4 as fluorinating reagent. The inexpensive ionic amphiphile sodium dodecyl sulfate (SDS) was found to be an excellent promoter for fluorofunctionalization of hydrophobic ketones without prior activation or use of acid catalysts. Georg Thieme Verlag Stuttgart.
Alkylation and decarboxylation of ethyl 2-fluoro-3-oxobutanoate as a route to functionalised α-fluoro-ketones
Hutchinson,Sandford, Graham,Vaughan, Julian F.S.
, p. 2867 - 2876 (2007/10/03)
Alkylation and decarboxylation of α-fluoro-β-ketoesters such as ethyl 2-fluoro-3-oxobutanoate offers a versatile route to a range of fluoro-ketoalkenes, demonstrating the synthetic utility of using α-fluoro-β-ketoesters as synthons for the preparation of synthetically more sophisticated selectively fluorinated systems.
Synthesis, Regioselective Deprotonation, and Stereoselective Alkylation of Fluoro Ketimines
Welch, John T.,Seper, Karl W.
, p. 2991 - 2999 (2007/10/02)
Fluoroacetone imines of cyclohexylamine, valinol O-methyl ether, and phenylalaninol O-methyl ether and 2-fluorocyclohexanone imines of cyclohexylamine and phenylalaninol O-methyl ether were prepared.The temperature-dependent, regioselective deprotonation of these imines was employed in highly regioselective alkylation reactions.The deprotonation of fluoroacetone cyclohexylimine on the carbon bearing fluorine yielded only a single stereoisomer as determined by low temperature 19F NMR.In contrast, deprotonation of fluoroacetone O-benzyloximes was not regiospecific under any of the conditions examined.
The Temperature-Dependent Regioselective Deprotonation of Fluoroacetone Cyclohexylimine
Welch, John T.,Seper, Karl W.
, p. 119 - 120 (2007/10/02)
The temperature-dependent regioselective deprotonation of fluoroacetone cyclohexylimine was developed as a procedure for the regioselective alkylation of fluoroacetone.
