über die Reaktionen von (CH3)4N+I-, (CH3)4N+ICl2-, (CH3)4N+ICl4- und (CH3)4N+Cl-mit Trifluormethylhypochlorit CF3OCl / The Reactions of (CH3)4N+I-, ( CH3)4N+ICl2-, (CH3)4N+ICl4- 和 (CH3)4N+Cl- 与三氟甲基次氯酸盐 CF3OCl
nucleophilic substitution is the dominant degradation pathway in NHAs, while Hofmann elimination is the primary degradation pathway for NHA-based AEMs. Different degradation pathways determine the alkaline stability of NHAs or NHA-based AEMs. AEMFC durability (from 1 A cm−2 to 3 A cm−2) suggests that NHA-based AEMs are mainly subjected to Hofmann elimination under 1 A cm−2 current density for 1000 h, providing
N-杂环铵 (NHA) 基团的碱性稳定性是阴离子交换膜 (AEM) 和 AEM 燃料电池 (AEMFC) 的关键课题。在这里,我们报告了对 24 个代表性 NHA 基团在不同水合数(λ) 在 80 °C。结果表明,含有给电子基团的 γ 取代 NHA 显示出优异的碱性稳定性,而吸电子取代基对耐久的 NHA 有害。密度泛函理论计算和实验结果表明,亲核取代是 NHA 的主要降解途径,而霍夫曼消除是基于 NHA 的 AEM 的主要降解途径。不同的降解途径决定了 NHA 或基于 NHA 的 AEM 的碱性稳定性。AEMFC 耐久性(从 1 A cm -2到 3 A cm -2)表明基于 NHA 的 AEM 主要在 1 A cm -2电流密度下进行 1000 小时的霍夫曼消除,从而深入了解电流密度与λ之间的关系 基于 NHA 的 AEM 的价值和耐久性。
Carbonylation of quaternary ammonium salts to tertiary amides using NaCo(CO)4 catalyst
作者:Yizhu Lei、Rui Zhang、Qing Wu、Hui Mei、Bo Xiao、Guangxing Li
DOI:10.1016/j.molcata.2013.10.014
日期:2014.1
the catalytic carbonylation of quaternary ammoniumsalts under anhydrous condition. Quaternary ammoniumsalts, a kind of versatile reagents that were widely used in organometallic chemistry, can be carbonylated to tertiaryamides by an in situ prepared NaCo(CO)4 catalyst. It was found that the counterions (Cl−, Br−, I−, OTf−) in the quaternary ammoniumsalts played a significant role in the reaction
Palladium-catalyzed carbonylation of quaternary ammonium halides to tertiary amides
作者:Yizhu Lei、Rui Zhang、Linjuan Wu、Qing Wu、Hui Mei、Guangxing Li
DOI:10.1002/aoc.3126
日期:2014.4
anhydrous conditions was investigated using palladium catalyst. The carbonylation of tetramethylammonium iodide was chosen as a model reaction and studied systematically. Ligand‐free PdCl2 showed efficient catalytic performance for this transformation. A palladium catalyst loading as low as 0.05 mol% was sufficient for high yield (96.9%) of N,N‐dimethylacetamide, corresponding to a turnover frequency
A process for producing a urethane compound which comprises reacting at least one compound selected from the group consisting of a primary amine, a secondary amine and a urea compound with carbon monoxide and an organic hydroxyl compound in the presence of a catalyst system comprising: (a) at least one member selected from the group consisting of platinum group metals and compounds containing at least one platinum group element; and (b) at least one halogen-containing compound selected from the group consisting of alkali or alkaline earth metal halides, onium halides, compounds capable of forming onium halides in the reaction, oxo acids of halogen atoms and their salts, complex compounds containing halogen ions, organic halides and halogen molecules, in the presence of molecular oxygen and/or an organic nitro compound as an oxidizing agent at a temperature of from about 80.degree. C. to about 300.degree. C. under a pressure of from about 1 Kg/cm.sup.2 to about 500 Kg/cm.sup.2.
Anion radical salts of bis[1,2,5]thiadiazolotetracyanoquinodimethan (BTDA) containing forty kinds of alkylammonium ions were prepared whose molar ratios are unique for each cation and changed from 1:1 (2A–2L) to 2:3 (2M–2Z), 1:2 (2a–2m), and 2:5 (2n) with elongation of the side chains. The electrical conductivities of the salts are largely affected by the molar ratio and the spatial requirement of