205-43-6Relevant articles and documents
Synthesis method of benzo[b] naphtho [2,3-d] thiophene
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Paragraph 0056-0058; 0071-0074; 0085-0087; 0098-0099; .., (2022/03/27)
The present invention discloses a method for synthesizing benzo [b] naphthio [2,3-d] thiophene, comprising the following steps: 2-aminobenzo [d] thiazole as a raw material, under the action of alkali and haloalkanes, to prepare 2- (methylthio) aniline; using 2- (methylthio) aniline to prepare (2-iophenyl) (methyl) thiane preparation of 1-iodo-2-(methylsulfonyl) benzene; using 1-iodo-2-(methylsulfonyl) benzene; using 1-iodo-2-(methylsulfonyl) Benzene and compound S5 were prepared to obtain 1-(2-(methyl sulfoxide phenyl)) naphthalene, and 1-(2-(methyl sulfoxidephenyl)) naphthalene was used to obtain benzo[b]naphthalene [2,3-d]thiophene. The present invention employs a green route to obtain high yield, high quality benzo [b] naphthalene [2,3-d] thiophene.
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.
Br?nsted Acid-Catalyzed Carbonyl-Olefin Metathesis: Synthesis of Phenanthrenes via Phosphomolybdic Acid as a Catalyst
Chen, Yi,Jin, Yuan,Lin, Zhihua,Liu, Di,Shu, Mao,Tan, Jingyao,Tian, Lingfeng,Wang, Rui,Xu, Li,Zhang, Xiaoke
, (2022/01/03)
Compared with the impressive achievements of catalytic carbonyl-olefin metathesis (CCOM) mediated by Lewis acid catalysts, exploration of the CCOM through Br?nsted acid-catalyzed approaches remains quite challenging. Herein, we disclose a synthetic protocol for the construction of a valuable polycycle scaffold through the CCOM with the inexpensive, nontoxic phosphomolybdic acid as a catalyst. The current annulations could realize carbonyl-olefin, carbonyl-alcohol, and acetal-alcohol in situ CCOM reactions and feature mild reaction conditions, simple manipulation, and scalability, making this strategy a promising alternative to the Lewis acid-catalyzed COM reaction.