507477-14-7Relevant academic research and scientific papers
Ru(II)-Catalyzed Asymmetric Transfer Hydrogenation of 3-Fluorochromanone Derivatives to Access Enantioenriched cis-3-Fluorochroman-4-ols through Dynamic Kinetic Resolution
Betancourt, Ricardo Molina,Phansavath, Phannarath,Ratovelomanana-Vidal, Virginie
, p. 12054 - 12063 (2021)
Enantioenriched cis-3-fluoro-chroman-4-ol derivatives were conveniently prepared by the ruthenium-catalyzed asymmetric transfer hydrogenation of a new family of 3-fluoro-chromanones through a dynamic kinetic resolution process. The reaction proceeded under mild conditions using a low catalyst loading and HCO2H/Et3N (1:1) as the hydrogen source, affording the reduced fluorinated alcohols in good yields (80-96%), high diastereomeric ratios (up to 99:1 dr), and excellent enantioselectivities (up to >99% ee).
Chiral FLP-catalyzed asymmetric hydrogenation of 3-fluorinated chromones
Dai, Yun,Du, Haifeng,Feng, Xiangqing,Meng, Wei
, p. 1558 - 1560 (2022/02/11)
The asymmetric hydrogenation of fluorinated olefins is an efficient pathway towards the synthesis of chiral fluorine-containing compounds. This paper described metal-free asymmetric hydrogenation of 3-fluorinated chromones with the use of readily availabl
Bench-Stable Electrophilic Fluorinating Reagents for Highly Selective Mono- and Difluorination of Silyl Enol Ethers
Adachi, Akiya,Aikawa, Kohsuke,Ishibashi, Yuichiro,Nozaki, Kyoko,Okazoe, Takashi
supporting information, p. 11919 - 11925 (2021/07/02)
Efficient methods for the synthesis of fluorinated compounds have been intensively studied, recently. Development of practical fluorinating reagents is indispensable for this purpose. Herein, bench-stable electrophilic fluorinating reagents were synthesized as N-fluorobenzenesulfonimide (NFSI) substitutes. Reagents obtained by replacing one of the NFSI sulfonyl groups with an acyl group led to the highly selective monofluorination of silyl enol ethers with suppression of undesired overreaction, that is, difluorination. On the other hand, reagents bearing electron-withdrawing substituents at NFSI benzenesulfonyl groups efficiently facilitated the difluorination of silyl enol ethers under base-free conditions. Thus, both mono- and difluorinated target materials were prepared from the same substrate.
A diastereoselective Mannich reaction of α-fluoroketones with ketimines: Construction of β-fluoroamine motifs with vicinal tetrasubstituted stereocenters
Zhao, Jian-bo,Ren, Xinfeng,Zheng, Bu-quan,Ji, Jian,Qiu, Zi-bin,Li, Ya
supporting information, p. 2091 - 2094 (2018/05/04)
A diastereoselective Mannich reaction has been developed for the synthesis of chiral β-fluoroamine motifs by the reaction of α-fluoroketones with ketimines, including isatin-derived ketimines and phenylglyoxylate-derived ketimines. This method provides a
Exploiting a Difference in Leaving Group Ability: An Approach to β-Substituted Monofluoroalkenes Using gem-Chlorofluoropropenes
Hamel, Jean-Denys,Cloutier, Mélissa,Paquin, Jean-Fran?ois
supporting information, p. 1852 - 1855 (2016/05/19)
The superior nucleofuge character of chlorine over fluorine was taken advantage of in the selective SN2′ substitution reaction of gem-chlorofluoropropenes, allowing for the clean formation of β-substituted monofluoroalkenes under metal-free conditions. Numerous N-, S-, O-, and C-nucleophiles behaved nicely in this system. Further synthetic transformations of selected monofluoroalkenes were also accomplished.
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).
Fluorinated aromatic ketones as nucleophiles in the asymmetric organocatalytic formation of C-C and C-N bonds: A facile route to the construction of fluorinated quaternary stereogenic centers
Zhao, Yujun,Pan, Yuanhang,Liu, Hongjun,Yang, Yuanyong,Jiang, Zhiyong,Tan, Choon-Hong
supporting information; experimental part, p. 3571 - 3574 (2011/05/05)
Highly enantioselective Mannich and α-amination reactions have been successfully developed using α-fluorinated aromatic ketones as fluorocarbon nucleophiles in the presence of a bicyclic chiral guanidine (see scheme; Ms=methanesulfonyl). This method is a
Direct α-fluorination of ketones using N-F reagents
Stavber, Stojan,Jereb, Marjan,Zupan, Marko
, p. 2609 - 2615 (2007/10/03)
The use of 1-fluoro-4-hydroxy-1,4-diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate) (Accufluor NFTh) as a fluorine atom transfer reagent and methanol as solvent enabled direct regiospecific fluorofunctionalization of the α-carbonyl position in ketones w
