Palladium‐Catalyzed Reductive Carbonylation of (Hetero) Aryl Halides and Triflates Using Cobalt Carbonyl as CO Source
作者:Bhushanarao Dogga、C. S. Ananda Kumar、Jayan T. Joseph
DOI:10.1002/ejoc.202001328
日期:2021.1.15
A generalized protocol for the reductive carbonylation of (hetero) aryl halides and triflates under CO gas‐free conditions using Pd/Co2(CO)8 and triethylsilane has been developed. The mild reaction conditions, enhanced safety, and wide substrate scope highlight its importance in routine organic synthesis.
已经开发了一种通用协议,用于在无CO气体条件下使用Pd / Co 2(CO)8和三乙基硅烷对(杂)芳基卤化物和三氟甲磺酸进行还原羰基化。温和的反应条件,增强的安全性和广泛的底物范围突出了其在常规有机合成中的重要性。
Sustainable Ligand‐Free, Palladium‐Catalyzed Suzuki–Miyaura Reactions in Water: Insights into the Role of Base
to acting as a base during the catalytic process. In the catalyticsystem with a strong base, the soluble active PdII ion exhibited anti-reduction properties, which prevented aggregation and deactivation of Pd species. The entire catalyticsystem could be recycled after separating the product by simple filtration. The water-compatible and air-stable effective catalytic protocol described herein represents
Ligand-free palladium acetate and palladium chloride have been evaluated as catalysts in the Suzukicross-coupling of aryl boronic acid with aryl and vinyl bromide in ethanol at room temperature and with exposure to air. The substrates with a wide variety of functional groups, including base-sensitive ones are tolerated.
[Pd(Cl)2{P(NC5H10)(C6H11)2}2]-A Highly Effective and Extremely Versatile Palladium-Based Negishi Catalyst that Efficiently and Reliably Operates at Low Catalyst Loadings
作者:Jeanne L. Bolliger、Christian M. Frech
DOI:10.1002/chem.201001201
日期:——
electronically activated, non‐activated, deactivated, stericallyhindered, heterocyclic, and functionalized aryl bromides with various (also heterocyclic) arylzinc reagents, typically within a few minutes at 100 °C in the presence of just 0.01 mol % of catalyst. Aryl bromides containing nitro, nitrile, ether, ester, hydroxy, carbonyl, and carboxyl groups, as well as acetals, lactones, amides, anilines,
[Pd(Cl)2 P(NC 5 H 10)(C 6 H 11)2 } 2 ](1)已通过使市售的[Pd(cod)(Cl)2 ]反应定量制备。室温下在几分钟内在N 2中与易于制备的1-(二环己基膦酰基)哌啶在甲苯中的环辛二烯)。综合大楼1已被证明是极佳的Negishi催化剂,能够将各种电子活化,非活化,失活,空间受阻,杂环和官能化的芳基溴化物与各种(也是杂环的)芳基锌试剂定量偶联,通常在几分钟内即可完成。 100°C,仅存在0.01 mol%的催化剂。含有硝基,腈,醚,酯,羟基,羰基和羧基的芳基溴化物,以及缩醛,内酯,酰胺,苯胺,烯烃,羧酸,乙酸,吡啶和嘧啶已被成功用作偶联伙伴。此外,在两个反应伙伴中都可以容忍电子和空间变化。实验观察强烈表明分子机制是有效的。
Diastereodivergent [3 + 2] Annulation of Aromatic Aldimines with Alkenes via C–H Activation by Half-Sandwich Rare-Earth Catalysts
multiple stereocenters from the same set of starting materials. We report herein the first diastereodivergent [3+2] annulation of aromatic aldimines with alkenes via C-H activation by half-sandwich rare-earth catalysts. This protocol provides an efficient and general route for the selective synthesis of both trans and cis diastereoisomers of multi-substituted 1-aminoindanes from the same set of aldimines