834-89-9Relevant articles and documents
Cu(I)/Chiral Bisoxazoline-Catalyzed Enantioselective Doyle-Kirmse Reaction of Allenyl Sulfides with α-Diazoesters
Li, Shu-Sen,Wang, Jianbo,Wang, Kang
supporting information, (2022/03/17)
Herein, a Cu(I)-catalyzed enantioselective Doyle-Kirmse reaction of allenyl sulfides and α-diazoesters is reported, which provides an efficient synthetic route to enantio-enriched chiral tertiary homopropargylic sulfides. This reaction features high enantioselectivities (up to 96 % ee) and good functional group tolerance. The alkyl substituted α-diazoester has also been demonstrated as the efficient substrates in the asymmetric Doyle-Kirmse reaction. Mechanistic studies, including kinetic experiments, were conducted to gain insights into the details of the reaction pathway. The potential synthetic utility of this protocol has also been demonstrated.
Copper-Catalyzed Direct C-H Alkylation of Polyfluoroarenes by Using Hydrocarbons as an Alkylating Source
Xie, Weilong,Heo, Joon,Kim, Dongwook,Chang, Sukbok
supporting information, p. 7487 - 7496 (2020/08/06)
Construction of carbon-carbon bonds is one of the most important tools in chemical synthesis. In the previously established cross-coupling reactions, prefunctionalized starting materials were usually employed in the form of aryl or alkyl (pseudo)halides or their metalated derivatives. However, the direct use of arenes and alkanes via a 2-fold oxidative C-H bond activation strategy to access chemoselective C(sp2)-C(sp3) cross-couplings is highly challenging due to the low reactivity of carbon-hydrogen (C-H) bonds and the difficulty in suppressing side reactions such as homocouplings. Herein, we present the new development of a copper-catalyzed cross-dehydrogenative coupling of polyfluoroarenes with alkanes under mild conditions. Relatively weak sp3 C-H bonds at the benzylic or allylic positions, and nonactivated hydrocarbons could be alkylated by the newly developed catalyst system. A moderate-to-high site selectivity was observed among various C-H bonds present in hydrocarbon reactants, including gaseous feedstocks and complex molecules. Mechanistic information was obtained by performing combined experimental and computational studies to reveal that the copper catalyst plays a dual role in activating both alkane sp3 C-H bonds and sp2 polyfluoroarene C-H bonds. It was also suggested that the noncovalent π-πinteraction and weak hydrogen bonds formed in situ between the optimal ligand and arene substrates are key to facilitating the current coupling reactions.
Method for preparing fluorinated aromatic hydrocarbons by photo/nickle concerted catalysis
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Paragraph 0021; 0022; 0024; 0029-0032, (2018/09/11)
The invention discloses a method for preparing fluorinated aromatic hydrocarbons by photo/nickle concerted catalysis. According to the method, cheap metal nickel salt is used as a catalyst, adding ofa ligand is not needed, and the catalyst cooperates with trace photosensitizer in visible light radiation to catalyze a fluoro aryl zinc reagent and an aryl halide to generate Negishi cross-coupling,so as to prepare a fluorinated aromatic hydrocarbons compound. The coupling reaction functional group is good in tolerance, a substrate is wide in applicability, and multiple fluorinated aromatic hydrocarbons compounds (80-96%) can be obtained at high yield in a near room temperature. Compared with a palladium catalysis system reported in the literature, the photo-nickle concerted catalysis systemadopted by the method disclosed by the invention has the advantages that the use amount of the photosensitizer is low, a nickel catalyst is low in price, expensive ligand does not need to be added, and environment-friendly, economical and practical effects are achieved; by combining with a flowing synthesis technology, the method can easily realize automatic synthesis of important fluorinated aromatic hydrocarbons compounds.
