描述了1-(二芳基甲基)-2-异硫氰酸根合苯到2,4-二芳基-4 H -3,1-苯并噻嗪衍生物的新的重排。在Friedel-Crafts条件下用三氯化铝处理起始化合物导致芳基取代基通过亲电的ipso取代机理迁移,然后环化形成3,1-苯并噻嗪环。预期的分子内硫代氨基甲酰化反应也会发生,并且5,11-dihydro-6 H -dibenzo [ b,e分离出[]氮杂-5-硫酮副产物。讨论了影响反应机理和选择性的因素。还合成了相应的1-(芳基甲基)-2-异硫氰酸根合苯衍生物,并研究了它们在Friedel-Crafts反应条件下的行为,以证实中间体二苯甲基/苄基阳离子的稳定性在确定反应过程中的关键作用。 1-(二芳基甲基)-2-异硫氰酸根合苯-Friedel-Crafts-重排-芳基迁移-3,1-苯并噻嗪
DOI:
10.1055/s-0029-1217399
作为产物:
描述:
邻苯二甲醚 、 邻硝基苯甲醛 在
silica-coated magnetic nanoparticles modified with polyphosphoric acid 作用下,
以
N,N-二甲基甲酰胺 为溶剂,
反应 5.0h,
以86%的产率得到4,4′-((2-nitrophenyl)methylene)bis(1,2-dimethoxybenzene)
Niobium Pentachloride Mediated Direct Bradsher-Type Reaction: A Rapid and Efficient Strategy to Synthesize Novel Substituted 9-Anthraldehydes
作者:Paulo M. Donate、Giovanni S. Baviera
DOI:10.1055/s-0041-1738445
日期:2023.10
Dichloromethyl methyl ether in the presence of niobium pentachloride and activated triarylmethanes leads to an efficient, mild, and rapid one-pot synthesis of several 9-anthraldehyde derivatives via a direct Bradsher-type reaction. This practical methodology offers several advantages, such as a broad substrate scope, simple workup process, and excellent yields.
Brønsted- and Lewis acid-catalyzed cyclization giving rise to substituted anthracenes and acridines
作者:Raf Goossens、Mario Smet、Wim Dehaen
DOI:10.1016/s0040-4039(02)01462-4
日期:2002.9
A versatile acid-catalyzed method for the preparation of symmetrically and unsymmetrically Substituted 9,10-diphenyl-anthracenes is explored. Diveratrylmethanes are prepared and converted into 10-plenylanthracene-9-carbaldehydes by Lewis acid catalysis and into 9-phenylacridines by reduction. (C) 2002 Elsevier Science Ltd. All rights reserved.
Aromatic ring transfer—a new synthesis of 2,4-diaryl-4H-3,1-benzothiazines
作者:Vladimir T. Abaev、Fatima A. Tsiunchik、Andrey V. Gutnov、Alexander V. Butin
DOI:10.1016/j.tetlet.2006.04.010
日期:2006.6
A new synthetic approach to 2,4-diaryl-4H-3,1-benzothiazines is described based on the rearrangement of 2-isothiocyano triarylmethanes in the presence of AlCl3. An aryl ring is found to migrate to the carbon atom of an isothiocyano group followed by intramolecular cyclization as a result of electrophilic attack of the benzhydryl carbocation on the sulfur atom. (c) 2006 Elsevier Ltd. All rights reserved.