74670-68-1Relevant academic research and scientific papers
Decarboxylative julia-kocienski gem-difluoro-olefination of 2-pyridinyl sulfonyldifluoroacetate
Wang, Xiao-Ping,Lin, Jin-Hong,Xiao, Ji-Chang,Zheng, Xing
, p. 928 - 932 (2014)
The decarboxylation of potassium 2-pyridinyl sulfonyldifluoroacetate and its subsequent reaction with aldehydes was found to be an efficient approach for the Julia-Kocienski reaction under mild conditions to give gem-difluoro olefins in moderate to excell
Stereoselective formation of Z-monofluoroalkenes by nickel-catalyzed defluorinative coupling of gem?difluoroalkenes with lithium organoborates
Huang, Weichen,Shen, Qilong,Xiao, Yisa
supporting information, (2022/02/02)
A method for stereoselective construction of Z-monofluoroalkenes by nickel-catalyzed defluorinative coupling of gem?difluoroalkenes in mild conditions was described. The combination of lithium organoborate and ZnBr2 generated in situ lithium ar
Fluoride-Triggered Synthesis of 1-Aryl-2,2-difluoroalkenes via Desilylative Defluorination of (1-Aryl)-2,2,2-trifluoroethyl-silanes
Carreras, Virginie,Ollevier, Thierry
, p. 13160 - 13168 (2021/09/18)
An efficient route for the synthesis of 1-aryl-2,2-difluoroalkenes via 1,2-desilylative defluorination is disclosed. Only a catalytic amount of fluoride source is required to initiate the desilylation and afford gem-difluoroalkenes in very good to quantitative yields, using mild reaction conditions in dimethyl carbonate as a green solvent. This reaction uses (1-aryl)-2,2,2-trifluoroethyl-silanes, which are easily prepared via the insertion reaction of trifluoroethyl diazo alkanes into the Si-H bond of tertiary organosilanes. (1-Aryl)-perfluoroalkyl-silanes cleanly afford the corresponding (Z)-1-benzylideneperfluoroalkanes, which upon hydrodefluorination furnish the (E)-β(perfluoroalkyl)styrene derivatives with excellent yield and complete stereoselectivity. A one-pot system involving sequential insertion and desilylative-defluorination is also suitable for this transformation. This method demonstrates the usefulness of organosilanes toward the preparation of fluorinated alkenes as synthetically useful targets.
Acid-Catalyzed Hydrothiolation of gem-Difluorostyrenes to Access α,α-Difluoroalkylthioethers
Sorrentino, Jacob P.,Orsi, Douglas L.,Altman, Ryan A.
, p. 2297 - 2311 (2021/02/06)
The substitution of hydrogen atoms with fluorine in bioactive molecules can greatly impact physicochemical, pharmacokinetic, and pharmacodynamic properties. However, current synthetic methods cannot readily access many fluorinated motifs, which impedes utilization of these groups. Thus, the development of new methods to introduce fluorinated functional groups is critical for developing the next generation of biological probes and therapeutic agents. The synthesis of one such substructure, the α,α-difluoroalkylthioether, typically requires specialized conditions that necessitate early-stage installation. A late-stage and convergent approach to access α,α-difluoroalkylthioethers could involve nucleophilic addition of thiols across gem-difluorostyrenes. Unfortunately, under basic conditions, nucleophilic addition to gem-difluorostyrenes generates an anionic intermediate that can undergo facile elimination of fluoride to generate α-fluorovinylthioethers. To overcome this decomposition, we herein exploit an acid-based catalyst system to facilitate simultaneous nucleophilic addition and protonation of the unstable intermediate. Ultimately, the optimized mild conditions afford the desired α,α-difluoroalkylthioethers in high selectivity and moderate to excellent yields. These α,α-difluoroalkylthioethers are less nucleophilic and more oxidatively stable relative to nonfluorinated thioethers, suggesting the potential application of this unexplored functional group in biological probes and therapeutic agents.
-Annulation of gem-Difluoroalkenes and Pyridinium Ylides: Access to Functionalized 2-Fluoroindolizines
Zhang, Jun-Qi,Hu, Dandan,Song, Jinyu,Ren, Hongjun
, p. 4646 - 4660 (2021/04/06)
A [3 + 2]-annulation of gem-difluoroalkenes and pyridinium ylides was developed employing ambient air as the sole oxidant in an open-vessel manner, affording a series of multifunctionalized 2-fluoroindolizines in moderate to good yields. In this reaction, gem-difluoroalkene acts as a C2 synthon and entirely avoids the competitive addition-elimination process, which provides facile access to 2-fluoroindolizines.
A one-step synthesis of gem-difluoroolefins from alcohols
Gu, Jinying,Lin, Jin-Hong,Tang, Ting,Xiao, Can,Xiao, Ji-Chang,Xiao, Xuan,Yao, Xu,Yu, Jiao,Zheng, Xing
, (2020/10/09)
The development of efficient protocols for the synthesis of gem-difluoroolefins has received increasing attention. Given the ubiquity of hydroxyl group in biologically active molecules and synthetic intermediates, we developed a one-step protocol for the conversions of alcohols into gem-difluoroolefins. The reactions of alcohols with Ph3P+CF2CO2?/Burgess reagent in DMSO occurred smoothly to afford the final products in moderate to high yields. DMSO is not only necessary for the oxidation process, but also important for the stabilization of phosphonium ylide by trapping difluorocarbene.
Design and Synthesis of TY-Phos and Application in Palladium-Catalyzed Enantioselective Fluoroarylation of gem-Difluoroalkenes
Li, Zhiming,Lin, Tao-Yan,Liu, Yu,Pan, Zhangjin,Tu, Youshao,Wu, Hai-Hong,Zhang, Junliang,Zhu, Shuai
supporting information, p. 22957 - 22962 (2020/10/19)
The first example of highly enantioselective fluoroarylation of gem-difluoroalkenes with aryl halides is presented by using a new chiral sulfinamide phosphine (Sadphos) type ligand TY-Phos. N-Me-TY-Phos can be easily synthesized on a gram scale from readily available starting materials in three steps. Salient features of this work including readily available starting materials, good yields, high enantioselectivities as well as broad substrate scope make this approach very practical and attractive. Notably, the asymmetric synthesis of an analogue of a biologically active molecule is also reported.
Organocatalytic Nucleophilic Substitution Reaction of gem-Difluoroalkenes with Ketene Silyl Acetals
Kondoh, Azusa,Koda, Kazumi,Terada, Masahiro
supporting information, p. 2277 - 2280 (2019/03/26)
An organocatalytic nucleophilic substitution reaction of gem-difluoroalkenes with ketene silyl acetals was developed. Phosphazene P4-tBu effectively catalyzed the reaction under mild conditions to provide monofluoroalkenes possessing an alkoxycarbonylmethyl group in high yields with high Z selectivities.
Regio- and Stereoselective Alkenylation of Allenoates with gem-Difluoroalkenes: Facile Access to Fluorinated 1,4-Enynes Bearing an All-Carbon Quaternary Center
Zhang, Qi-Qi,Chen, Shi-Yong,Lin,Wang, Honggen,Li, Qingjiang
supporting information, p. 3123 - 3126 (2019/05/02)
A regio- and stereoselective synthesis of fluorinated 1,4-enynes bearing an all-carbon quaternary center at the propargylic position is developed. The synthesis starts from readily available allenoates and gem-difluoroalkenes and proceeds via a key alkyny
Rhodium-Catalyzed Defluorinative Vinylation of gem-Difluoroalkenes for the Synthesis of 2-Fluoro-1,3-dienes
Song, Shengjin,Liu, Huan,Wang, Lu,Zhu, Chuan,Loh, Teck-Peng,Feng, Chao
supporting information, p. 1036 - 1040 (2019/09/16)
Herein, we present a strategy for the formation of 2-fluoro-1,3-diene derivatives via rhodium-catalyzed direct C(sp2)—C(sp2) cross-coupling of gem-difluoroalkenes and acrylamides. By merging Rh(III)-catalyzed C(sp2)–H bond activation and nucleophilic addition/F-elimination of gem-difluoroalkene, an efficient defluorinative vinylation reaction is uncovered, which leads to the generation of 2-fluoro-1,3-dienes in moderate to good yields with excellent stereoselectivity under mild conditions. Preliminary mechanistic study suggests unique effects of fluorine substituents which allow the reactivity profile not observed with the congeners bearing heavier halides.
