A light-promoted Ni-catalyzed cyanation of arylhalides employing 1,4-dicyanobenzene as a cyanating agent is reported. A broad array of aryl bromides, chlorides, and druglike molecules could be converted into their corresponding nitriles (65 examples). Mechanistic studies suggest that upon irradiation, the oxidative addition product Ni(II)(dtbbpy)(p-C6H4CN)(CN) undergoes homolytic cleavage of the Ni–aryl
报道了使用 1,4-二氰基苯作为氰化剂的光促进 Ni 催化的芳基卤化物氰化反应。广泛的芳基溴化物、氯化物和药物样分子可以转化为相应的腈(65 个例子)。机理研究表明,在辐照下,氧化加成产物 Ni(II)(dtbbpy)( p -C 6 H 4 CN)(CN) 发生 Ni-芳基键均裂,生成芳基自由基和 Ni(I) -CN 物质,后者引发随后的氰化反应。
General and Mild Nickel-Catalyzed Cyanation of Aryl/Heteroaryl Chlorides with Zn(CN)<sub>2</sub>: Key Roles of DMAP
作者:Xingjie Zhang、Aiyou Xia、Haoyi Chen、Yuanhong Liu
DOI:10.1021/acs.orglett.7b00732
日期:2017.4.21
A new and general nickel-catalyzed cyanation of hetero(aryl) chlorides using less toxic Zn(CN)2 as the cyanidesource has been developed. The reaction relies on the use of inexpensive NiCl2·6H2O/dppf/Zn as the catalytic system and DMAP as the additive, allowing the cyanation to occur under mild reaction conditions (50–80 °C) with wide functional group tolerance. DMAP was found to be crucial for successful
已经开发了一种新的且一般的镍催化的杂(芳基)氯化物氰化方法,该方法使用毒性较小的Zn(CN)2作为氰化物源。该反应依赖于使用廉价的NiCl 2 ·6H 2 O / dppf / Zn作为催化体系,并使用DMAP作为添加剂,从而使氰化反应在温和的反应条件下(50–80°C)发生,且具有宽泛的官能团耐受性。发现DMAP对于成功转化至关重要,并且基于机理研究,该反应可能通过Ni(0)/ Ni(II)催化进行。该方法也成功地扩展到了芳基溴化物和芳基碘化物。