525-82-6Relevant articles and documents
A novel one-pot synthesis of flavones
Chang, Meng-Yang,Tsai, Min-Chen,Lin, Chun-Yi
, p. 11655 - 11662 (2021/03/31)
In this paper, a one-pot facile route for the BiCl3/RuCl3-mediated synthesis of functionalized flavones is described, including: (i) intermolecularortho-acylation of substituted phenols with cinnamoyl chlorides, and (ii) intramolecular cyclodehydrogenation of the resultingo-hydroxychalcones. The reaction conditions are discussed herein.
Site-Selective Acceptorless Dehydrogenation of Aliphatics Enabled by Organophotoredox/Cobalt Dual Catalysis
Zhou, Min-Jie,Zhang, Lei,Liu, Guixia,Xu, Chen,Huang, Zheng
supporting information, p. 16470 - 16485 (2021/10/20)
The value of catalytic dehydrogenation of aliphatics (CDA) in organic synthesis has remained largely underexplored. Known homogeneous CDA systems often require the use of sacrificial hydrogen acceptors (or oxidants), precious metal catalysts, and harsh reaction conditions, thus limiting most existing methods to dehydrogenation of non- or low-functionalized alkanes. Here we describe a visible-light-driven, dual-catalyst system consisting of inexpensive organophotoredox and base-metal catalysts for room-temperature, acceptorless-CDA (Al-CDA). Initiated by photoexited 2-chloroanthraquinone, the process involves H atom transfer (HAT) of aliphatics to form alkyl radicals, which then react with cobaloxime to produce olefins and H2. This operationally simple method enables direct dehydrogenation of readily available chemical feedstocks to diversely functionalized olefins. For example, we demonstrate, for the first time, the oxidant-free desaturation of thioethers and amides to alkenyl sulfides and enamides, respectively. Moreover, the system's exceptional site selectivity and functional group tolerance are illustrated by late-stage dehydrogenation and synthesis of 14 biologically relevant molecules and pharmaceutical ingredients. Mechanistic studies have revealed a dual HAT process and provided insights into the origin of reactivity and site selectivity.
Continuous flow microchannel synthesis process of flavonoid compounds
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Paragraph 0050-0060, (2021/06/22)
The invention provides a continuous flow microchannel synthesis process of flavonoid compounds. According to the process, hesperidin and iodine elementary substance are used as raw materials and react in a continuous flow microchannel reactor in the presence of a reaction solvent to synthesize the flavonoid compound as shown in a formula A. Compared with a traditional kettle-type preparation process, the process disclosed by the invention has the advantages that the preparation time is obviously shortened, and the conversion rate of raw materials and the yield of products are obviously improved; and especially, when the diosmin is prepared under optimal process conditions of continuous flow microchannel synthesis, the conversion rate of the raw material hesperidin is as high as 96.48%, and the yield of the product diosmin is as high as 81.96%. The continuous flow micro-channel synthesis process provided by the invention is beneficial to realizing safe, efficient and rapid industrial production of flavonoid compounds, and has a wide application prospect.