Cobalt-Catalyzed Cross-Coupling Reactions of Heterocyclic Chlorides with Arylmagnesium Halides and of Polyfunctionalized Arylcopper Reagents with Aryl Bromides, Chlorides, Fluorides and Tosylates
A range of aromatic organocopper or organomagnesium compounds undergo smooth cross-coupling reactions with aryl bromides, chlorides, fluorides and tosylates, leading to polyfunctionalized aromatics or heterocycles in the presence of cobalt salts (5-7.5 mol%) as catalysts. Very mild reaction conditions are needed and, in the case of cross-coupling with organocopper compounds, Bu4NI (1 equiv) and 4-fluorostyrene (20 mol%) are essential as promoters for successful couplings.
Method of preparing an optical connector and optical devices comprising the optical connector prepared thereby
申请人:Dow Corning Corporation
公开号:US10551566B2
公开(公告)日:2020-02-04
A method of preparing an optical connector located within a gap between a first optical assembly and a second optical assembly is provided. The optical connector includes a contrast layer having at least one cured bridge portion and at least one uncured portion formed from a first composition having a first refractive index (RI1). The method comprises applying a second composition having a second refractive index (RI2) on the contrast layer to form a second layer and mixing at least a portion of the second layer with the at least one uncured portion of the contrast layer to form at least one intermixed portion having a third refractive index (RI3), wherein R|1>R|3>RI2, and then curing the intermixed portion and optional second layer such that each one of the at least one cured bridge portions is surrounded by an intermixed portion and optional second layer.
Iron-Catalyzed Aryl-Aryl Cross-Couplings with Magnesium-Derived Copper Reagents
作者:Ioannis Sapountzis、Wenwei Lin、Christiane C. Kofink、Christina Despotopoulou、Paul Knochel
DOI:10.1002/anie.200462013
日期:2005.3.4
Cobalt(II)-Catalyzed Cross-Coupling between Polyfunctional Arylcopper Reagents and Aryl Fluorides or Tosylates
作者:Tobias J. Korn、Matthias A. Schade、Stefan Wirth、Paul Knochel
DOI:10.1021/ol0529142
日期:2006.2.1
of functionalized arylmagnesium halides with CuCN.2LiCl undergo smooth cross-coupling reactions with aryl fluorides and tosylates bearing a carbonyl function in the ortho position in the presence of Co(acac)(2) (7.5 mol %), Bu(4)NI (1 equiv), and 4-fluorostyrene (20 mol %) as promoters in DME/THF/DMPU leading to polyfunctional aromatics or heterocycles.
Triethanolamine-based deep eutectic solvent as a novel, biocompatible, reusable, and efficient dual catalyst/solvent media for the selective tosylation and mesylation of phenols
作者:Fatemeh Abbasi、Ali Reza Sardarian
DOI:10.1016/j.tet.2023.133780
日期:2024.2
reusable catalyst/solvent system, was applied for the selective tosylation of phenols under mild conditions. This DES can easily be recycled up to four times without significantly affecting the reaction progress. The advantages of this protocol are the absence of any additives, ligands and metals, as well as the use of a dual solvent/catalyst system, which includes easy preparation, stability and reusability
低共熔溶剂(DES)通常由氢键供体和氢键受体组成,由于其可调性、生物可降解性和合成成本低,最近被广泛研究为各种应用的有效且有用的溶剂。在这项工作中,我们通过热重分析(TGA)、傅里叶变换红外光谱(FT-IR)、差示扫描量热法(DSC)制备并鉴定了[苄基(2-羟乙基)二甲基氯化氮][三乙醇胺] 2作为一种新型DES。 )、循环伏安法 (CV)、氢电位 (pH)、折射率、粘度和电导率。该DES是一种可重复使用的催化剂/溶剂系统,用于在温和条件下选择性对苯酚进行甲苯磺酰化。这种 DES 可以轻松回收四次,而不会显着影响反应进度。该方案的优点是不存在任何添加剂、配体和金属,以及使用双溶剂/催化剂系统,包括易于制备、稳定性和可重复使用性、反应时间短和优异的产物产率。