An Improved Catalyst System for the Pd-Catalyzed Fluorination of (Hetero)Aryl Triflates
摘要:
The stable Pd(0) species [(1,5-cyclooctadiene)(L.Pd)(2)] (L = AdBrettPhos) has been prepared and successfully evaluated as a precatalyst for the fluorination of aryl triflates derived from biologically active and heteroaryl phenols, challenging substrates for our previously reported catalyst system. Additionally, this precatalyst activates at room temperature under neutral conditions, generates 1,5-cyclooctadiene as the only byproduct, and leads to overall cleaner reaction profiles.
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。
Directed ortho Metalation (DoM)-Linked Corriu–Kumada, Negishi, and Suzuki–Miyaura Cross-Coupling Protocols: A Comparative Study
作者:Victor Snieckus、Claude Quesnelle
DOI:10.1055/s-0037-1611053
日期:2018.11
the DoM strategy lends itself to the regioselective construction of diversely substitutedaromatics and heteroaromatics. A systematic study of the widely used, titled name reaction transition-metal-catalyzed cross-coupling reactions with attention to context with the directed ortho metalation (DoM) is reported. In general, the Suzuki–Miyaura and Negishi protocols show greater scope and better yields
致力于斯科特丹麦:至此,我们(以及缺席的KB )正在庆祝您的创造力和成就。 发布时间作为的一部分奉献给斯科特E.丹麦在他65之际特别节日的生日。 抽象的 报告了对广泛使用的标题反应过渡金属催化的交叉偶联反应的系统研究,并着眼于定向原金属化(D o M)。通常,Suzuki-Miyaura和Negishi方案比Corriu-Kumada方案具有更大的范围和更高的产量,尽管后者定性地以最快的速度进行,但功能基团的耐受性较低。据证明,Negishi工艺可用于具有亲核试剂和碱敏感功能的底物,其效率可与Suzuki-Miyaura反应媲美。这些交叉偶联反应与D o M策略的联系使其适用于不同取代的芳族化合物和杂芳族化合物的区域选择性结构。 报告了对广泛使用的标题反应过渡金属催化的交叉偶联反应的系统研究,并着眼于定向原金属化(D o M)。通常,Suzuki-Miyaura和Negishi方案比Cor
Room Temperature Carbonylation of (Hetero) Aryl Pentafluorobenzenesulfonates and Triflates using Palladium-Cobalt Bimetallic Catalyst: Dual Role of Cobalt Carbonyl
作者:Jayan T. Joseph、Ayyiliath M. Sajith、Revanna C. Ningegowda、Sheena Shashikanth
DOI:10.1002/adsc.201600736
日期:2017.2.2
method for the carbonylation of (hetero) aryl pentafluorobenzenesulfonates and triflates under exceptionally mild conditions using palladium/dicobalt octacarbonyl [Pd/Co2(CO)8] has been developed. Besides acting as carbon monoxide (CO) source, Co2(CO)8 enhances the reaction rate by accelerating the CO insertion through an in situ generated bimetallic palladium cobalt tetracarbonyl [Pd‐Co(CO)4] complex
已经开发了一种在异常温和的条件下使用钯/二钴八羰基[Pd / Co 2(CO)8 ]对(杂)芳基五氟苯磺酸盐和三氟甲磺酸酯进行羰基化的有效方法。除了充当一氧化碳(CO)源外,Co 2(CO)8还可以通过原位生成的双金属钯四羰基钴[Pd-Co(CO)4)加速CO的插入,从而提高反应速率。] 复杂的。在优化的反应条件下,各种活化和失活的,以及位阻和杂芳族底物的羰基化反应在室温下均能有效进行。生物学上相关的异古瓦汀和拉扎贝米中间体的高化学选择性和改进的合成方法突出了其作为有价值的合成方法的范围。该协议的通用性进一步扩展到其他亲电试剂(溴化物,氯化物和甲苯磺酸盐)。
A Nickel-Catalyzed Carbonyl-Heck Reaction
作者:Jaya Kishore Vandavasi、XiYe Hua、Hamdi Ben Halima、Stephen G. Newman
DOI:10.1002/anie.201710241
日期:2017.11.27
The use of transition‐metal catalysis to enable the coupling of readily available organic molecules has greatly enhanced the ability of chemists to access complex chemical structures. In this work, an intermolecular coupling reaction that unites organotriflates and aldehydes is presented. A unique catalyst system is identified to enable this reaction, featuring a Ni0 precatalyst, a tridentate Triphos
A General, Multimetallic Cross-Ullmann Biheteroaryl Synthesis from Heteroaryl Halides and Heteroaryl Triflates
作者:Kai Kang、Nathan L. Loud、Tarah A. DiBenedetto、Daniel J. Weix
DOI:10.1021/jacs.1c10907
日期:2021.12.29
medicine and materials science, the synthesis of biheteroaryls by cross-coupling remains challenging. We describe here a new, general approach to biheteroaryls: the Ni- and Pd-catalyzed multimetallic cross-Ullmann coupling of heteroaryl halides with triflates. An array of 5-membered, 6-membered, and fused heteroaryl bromides and chlorides, as well as aryltriflates derived from heterocyclic phenols,