Efficient and Mild Ullmann-Type N-Arylation of Amides, Carbamates, and Azoles in Water
作者:Maud Bollenbach、Pedro G. V. Aquino、João Xavier de Araújo-Júnior、Jean-Jacques Bourguignon、Frédéric Bihel、Christophe Salomé、Patrick Wagner、Martine Schmitt
DOI:10.1002/chem.201700832
日期:2017.10.4
A simple, sustainable, efficient, mild, and low‐cost protocol was developed for d‐glucose‐assisted Cu‐catalyzed Ullmann reactions in water for amides, carbamates, and nitrogen‐containing heterocycles. The reaction was compatible with diverse aryl/heteroaryl iodides, giving highly substituted pyridine, indole, or indazole rings. This method offers an attractive alternative to existing protocols, because
decades of development, carbonylation reactions have become one of the most powerful tools in modern organic synthesis. However, the requirement of CO gas limits the applications of such reactions. Reported herein is a versatile and practical protocol for carbonylativereactions which rely on the cooperation of phenyl formate and nonaflate, and the generation of CO in situ. This protocol has a high functional‐group
Copper‐Catalyzed Mild Nitration of Protected Anilines
作者:Elier Hernando、Rafael R. Castillo、Nuria Rodríguez、Ramón Gómez Arrayás、Juan C. Carretero
DOI:10.1002/chem.201404000
日期:2014.10.20
A practical copper‐catalyzed direct nitration of protected anilines, by using one equivalent of nitric acid as the nitrating agent, has been developed. This procedure features mild reaction conditions, wide structural scope (with regard to both N‐protecting group and arene substitution), and high functional‐group tolerance. Dinitration with two equivalents of nitric acid is also feasible.
Palladium-Catalyzed C-H Cyclization in Water: A Milder Route to 2-Arylbenzothiazoles
作者:Kiyofumi Inamoto、Yoshinori Kondo、Kanako Nozawa
DOI:10.1055/s-0031-1291164
日期:2012.7
medium in palladium-catalyzed C–H cyclization of thiobenzanilides. Reactions efficiently proceeded under considerably mild conditions such as 40 °C in water, providing a more practical, greener method for the synthesis of 2-arylbenzothiazoles. For somesubstrates, the addition of an amphiphilic surfactant greatly enhanced the process. The method represents a rare example of palladium-catalyzed C–H functionalization
在钯催化的硫代苯甲酰苯胺的 C-H 环化中,水被成功用作反应介质。反应在相当温和的条件下有效进行,例如在 40 °C 的水中,为合成 2-芳基苯并噻唑提供了一种更实用、更环保的方法。对于某些基材,添加两亲性表面活性剂大大增强了该过程。该方法代表了在水中进行钯催化的 C-H 功能化过程的一个罕见例子。
Photoinduced Annulation of
<i>N</i>
‐Phenylbenzamides for the Synthesis of Phenanthridin‐6(5
<i>H</i>
)‐Ones
A general concise method for the synthesis phenanthridin-6(5H)-ones via photoinduced intramolecular annulation of N-phenylbenzamides was developed. Under argon atmosphere and room temperature, phenanthridin-6(5H)-ones were obtained via irradiation N-phenylbenzamides with a 280 nm UV lamp in the presence of methanesulfonic acid in toluene. The mechanism is illustrated and believed to proceed in the
开发了一种通过光诱导N-苯基苯甲酰胺分子内环化合成菲啶-6(5 H )-ones的通用简明方法。在氩气和室温下,在甲苯中甲磺酸存在下,通过用 280 nm 紫外灯照射N-苯基苯甲酰胺,得到菲啶-6(5 H )-酮。该机理被说明并认为按照酰胺互变异构、6π-电环化、[1,5]-H 位移、酰胺-亚胺互变异构、酮-烯醇互变异构和放氢的顺序进行。