1458680-29-9Relevant academic research and scientific papers
Visible Light-Promoted Phosphine-Catalyzed Difluoroalkylation of Arenes and Heterocycles
Lu, Heng,Wang, Dong-Yu,Zhang, Ao
, p. 942 - 951 (2020/02/04)
A visible light-promoted difluoroalkylation reaction of arenes or heterocycles, using triaryl phosphine as the catalyst and difluoroalkyl iodide as the alkylating agent, is presented. The strategy is highlighted by photocatalyst-free, mild reaction conditions and a broad substrate scope. Mechanistic experiments indicate that this reaction involves a radical-chain process that is initiated by an electron donor-acceptor complex formed from difluoroalkyl iodide and phosphine.
De novo Design of Organic Photocatalysts: Bithiophene Derivatives for the Visible-light Induced C?H Functionalization of Heteroarenes
Bottecchia, Cecilia,Martín, Raúl,Abdiaj, Irini,Crovini, Ettore,Alcazar, Jesús,Orduna, Jesús,Blesa, María Jesús,Carrillo, José R.,Prieto, Pilar,No?l, Timothy
supporting information, p. 945 - 950 (2019/01/25)
Herein, we report the de novo synthesis and characterization of a series of substituted bithiophene derivatives as novel and inexpensive organic photocatalysts. DFT calculations were used to predict a priori their absorption spectra and redox potentials, which were then confirmed with empirical data. The photocatalytic activity of this novel class of organic photoredox catalyst was demonstrated in two visible-light mediated strategies for the C?H functionalization of heteroarenes. The implementation of these strategies in a continuous-flow photo-microreactor afforded moderate to excellent yields within few minutes of reaction time. Due to their straightforward synthesis, low cost and good photocatalytic properties we believe that the proposed bithiophene derivatives could be employed as a new class of organic photoredox catalysts. (Figure presented.).
Method for synthesizing difluoroalkyl heterocyclic compound
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Paragraph 0037-0040, (2019/01/08)
The invention discloses a method for synthesizing a difluoroalkyl heterocyclic compound. The method comprises the steps of: under the protection of argon, selecting ethyl bromodifluoroacetate and heterocyclic compounds as starting materials, adding a suitable solvent and a certain amount of alkali, a nitric heterocyclic carbene precursor and a cobalt catalyst, performing stirring at a suitable temperature, adding a small amount of ethyl acetate after a reaction is completed, adding diatomaceous earth to a sand core funnel, pouring the obtained reaction mixture into the sand core funnel for filtration, performing washing and suction filtration by using ethyl acetate, performing vacuum concentration on mother liquid so as to obtain a coarse product, adopting a mixed solvent of petroleum ether and ethyl acetate as an eluate, performing column chromatography so as to obtain the target product. According to the method, no use of hazardous reagents is required, and the method has the characteristics of simple operation, economical raw materials and environmental friendliness.
Copper-Catalyzed C-H Difluoroalkylations and Perfluoroalkylations of Alkenes and (Hetero)arenes
Wang, Xiaoyang,Zhao, Shuang,Liu, Jing,Zhu, Dingsheng,Guo, Minjie,Tang, Xiangyang,Wang, Guangwei
supporting information, p. 4187 - 4190 (2017/08/23)
A general and facile synthetic method for C(sp2)-H difluoroalkylations and perfluoroalkylations of alkenes and (hetero)arenes with commercially available fluoroalkyl halides has been developed with a copper-amine catalyst system. This method is characterized by high yields, mild reaction conditions, low-cost catalyst, broad substrate scope, and excellent functional group compatibility, therefore providing a convenient synthetic strategy toward various difluoroalkyl- and perfluoroalkyl-substituted alkenes and (hetero)arenes.
Palladium-catalyzed C-H ethoxycarbonyldifluoromethylation of electron-rich heteroarenes
Shao, Changdong,Shi, Guangfa,Zhang, Yanghui,Pan, Shulei,Guan, Xiaohong
supporting information, p. 2652 - 2655 (2015/06/16)
The first Pd-catalyzed C-H ethoxycarbonyldifluoromethylation with BrCF2CO2Et has been developed. The use of a bidentate phosphine ligand (Xantphos) is critical for the reaction to occur. A variety of electron-rich heteroarenes, including indoles, furans, thiophenes, and pyrroles, can be ethoxycarbonyldifluoromethylated in moderate to excellent yields. The reactions take place at the C-H bonds adjacent to the heteroatoms with high regioselectivity. This method provides a new protocol for the introduction of difuoroalkyl groups into electron-rich heteroarenes.
Direct fluoroalkylation of indoles with fluoroalkyl halides mediated by copper
He, Ru-Yi,Zeng, Hui-Ting,Huang, Jing-Mei
supporting information, p. 4258 - 4263 (2014/07/21)
An efficient and mild copper-mediated reaction for the direct perfluoroalkylation and difluoromethylation of indoles with perfluoroalkyl halides and ICF2COOEt to produce 2-substituted indoles was developed. Both free indole derivatives and N-su
Visible Light-Induced Aromatic Difluoroalkylation
Jung, Jaehun,Kim, Eunjin,You, Youngmin,Cho, Eun Jin
supporting information, p. 2741 - 2748 (2016/02/18)
Difluoroalkylated aromatics are important structural motifs in pharmaceutical and agrochemical applications. Herein, we report their synthesis by a mild, efficient, and convenient method using visible light photoredox catalysis. A variety of unactivated aromatics were difluoroalkylated with ethyl 2-bromo-2,2-difluoroacetate (BrCF2CO2Et) in the presence of the triscyclometalated Ir complex fac-[Ir(ppy)3] under visible light irradiation at room temperature. It is shown that reaction outcomes containing the CF2CO2Et moiety can be converted to a variety of other CF2-containing aromatics, demonstrating the synthetic utility of the present method.
Rapid trifluoromethylation and perfluoroalkylation of five-membered heterocycles by photoredox catalysis in continuous flow
Straathof, Natan J. W.,Gemoets, Hannes P. L.,Wang, Xiao,Schouten, Jaap C.,Hessel, Volker,Noel, Timothy
, p. 1612 - 1617 (2014/07/08)
Trifluoromethylated and perfluoroalkylated heterocycles are important building blocks for the synthesis of numerous pharmaceutical products, agrochemicals and are widely applied in material sciences. To date, trifluoromethylated and perfluoroalkylated hetero-aromatic systems can be prepared utilizing visible light photoredox catalysis methodologies in batch. While several limitations are associated with these batch protocols, the application of microflow technology could greatly enhance and intensify these reactions. A simple and straightforward photocatalytic trifluoromethylation and perfluoroalkylation method has been developed in continuous microflow, using commercially available photocatalysts and microflow components. A selection of five-membered hetero-aromatics were successfully trifluoromethylated (12 examples) and perfluoroalkylated (5 examples) within several minutes (8-20 min). Photo workflow: A simple and straightforward photocatalytic method for perfluoroalkylation in continuous flow is developed. A photo-microreactor, constructed from commercially available components, enables accelerated photocatalysis employing [Ru(bpy)3Cl2] as photocatalyst under irradiation by blue LED light. A series of electron-rich hetero-aromatics is successfully trifluoromethylated within 8-16 min. Also, a selection of hetero-aromatics is perfluoroalkylated within 10-20 min.
Direct introduction of ethoxycarbonyldifluoromethyl-group to heteroarenes with ethyl bromodifluoroacetate via visible-light photocatalysis
Lin, Qingyu,Chu, Lingling,Qing, Feng-Ling
, p. 885 - 891 (2013/08/23)
A mild and versatile approach for the direct introduction of ethoxycarbonyldifluoromethyl-group to heteroarenes via visible-light photocatalysis has been developed. The new photoredox protocol has enabled the difluoromethylenation of heteroarenes containing a wide range of common functional groups under mild conditions. Copyright
