A series of chiral cyclometalated iridiumcomplexes have been synthesised by cyclometalating chiral 2-aryl-oxazoline and imidazoline ligands with [Cp*IrCl2]2. These iridacycles were studied for asymmetric transfer hydrogenation reactions with formic acid as the hydrogen source and were found to display various activities and enantioselectivities, with the most effective ones affording up to 63% ee
Copper-Catalyzed Oxidative [3 + 2] Cycloaddition of <i>N</i>-Alkyl Pyridinium Salts to Imidazo[1,2-<i>a</i>]pyridines
作者:Yuan Zhang、Weibin Fan、Yinghua Li、Deguang Huang
DOI:10.1021/acs.joc.3c00728
日期:2023.9.1
A copper-catalyzed reaction of pyridiniumsalts and trimethylsilyl cyanide (TMSCN) in the presence of diethyl phosphite is developed. This reaction, which allows the single-step construction of biologically important 2-cyanoimidazo[1,2-a]pyridine from readily available starting materials, is realized for the first time and is feasible at the gram scale. The scope of the protocol is demonstrated with
开发了在亚磷酸二乙酯存在下吡啶鎓盐和三甲基硅烷基氰化物 (TMSCN) 的铜催化反应。该反应首次实现了从容易获得的起始材料一步构建生物学上重要的2-氰基咪唑并[1,2- a ]吡啶的反应,并且在克级是可行的。该协议的范围通过 27 个示例进行了演示。在这一一锅法中可以实现连续的双氰化和环化。TMSCN 发挥双重作用,不仅作为“CN”源,而且作为咪唑并[1,2- a ]吡啶环化的偶联伙伴。