7012-16-0Relevant articles and documents
Preparation method for benflumetol and matched system thereof
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Paragraph 0041-0053, (2020/05/02)
The invention belongs to the field of benflumetol, and relates to preparation and a system for the benflumetol, in particular to a preparation method for the benflumetol and a matched system thereof.The preparation method for the benflumetol is completed by sequentially through bulk drugs, a plurality of intermediates and the benflumetol. The matched system for the preparation method sequentiallycomprises an intermediate I matched system, an intermediate II matched system, an intermediate IV matched system, an intermediate V matched system and a benflumetol matched system. According to the invention, overall preparation is simple, reasonable and highly-efficient; the required time is greatly shortened; and exploration of industrial production conditions of the benflumetol is completed.
Additive-Free Palladium-Catalyzed Decarboxylative Cross-Coupling of Aryl Chlorides
Daley, Ryan A.,Liu, En-Chih,Topczewski, Joseph J.
supporting information, p. 4734 - 4738 (2019/06/27)
The cross-coupling of sodium (hetero)aryl carboxylates with (hetero)aryl chlorides proceeds with 1 mol % palladium catalyst and does not require inorganic base, silver salts, or copper salts. This coupling uses two low energy partners, and the only stoichiometric byproducts are carbon dioxide and sodium chloride. The substrate scope includes less activated aryl chlorides and carboxylates (>25 examples). The palladium loading could be reduced to 0.1 mol %, and Buchwald-style precatalysts could be used.
Au-catalyzed biaryl coupling to generate 5- to 9-membered rings: Turnover-limiting reductive elimination versus π-complexation
Corrie, Tom J. A.,Ball, Liam T.,Russell, Christopher A.,Lloyd-Jones, Guy C.
, p. 245 - 254 (2017/05/29)
The intramolecular gold-catalyzed arylation of arenes by aryl-trimethylsilanes has been investigated from both mechanistic and preparative aspects. The reaction generates 5- to 9-membered rings, and of the 44 examples studied, 10 include a heteroatom (N, O). Tethering of the arene to the arylsilane provides not only a tool to probe the impact of the conformational flexibility of Ar-Au-Ar intermediates, via systematic modulation of the length of aryl-aryl linkage, but also the ability to arylate neutral and electron-poor arenes-substrates that do not react at all in the intermolecular process. Rendering the arylation intramolecular also results in phenomenologically simpler reaction kinetics, and overall these features have facilitated a detailed study of linear free energy relationships, kinetic isotope effects, and the first quantitative experimental data on the effects of aryl electron demand and conformational freedom on the rate of reductive elimination from diaryl-gold(III) species. The turnover-limiting step for the formation of a series of fluorene derivatives is sensitive to the reactivity of the arene and changes from reductive elimination to π-complexation for arenes bearing strongly electron-withdrawing substituents (σ > 0.43). Reductive elimination is accelerated by electron-donating substituents (ρ = -2.0) on one or both rings, with the individual σ-values being additive in nature. Longer and more flexible tethers between the two aryl rings result in faster reductive elimination from Ar-Au(X)-Ar and lead to the π-complexation of the arene by Ar-AuX2 becoming the turnover-limiting step.
