Conanoparticles (NPs) encapsulated in N‐dopedcarbonnanotubes (Co@NC900) are systematically investigated as a potential alternative to precious Pt‐group catalysts for hydrogenative heterocyclization reactions. Co@NC900 can efficiently catalyze hydrogenative coupling of 2‐nitroaniline to benzaldehyde for synthesis of 2‐phenyl‐1H‐benzo[d]imidazole with >99 % yield at ambient temperature in one step
Diversity-oriented synthesis of imidazo[2,1-<i>a</i>]isoquinolines
作者:Shaoyu Mai、Yixin Luo、Xianyun Huang、Zhenghao Shu、Bingnan Li、Yu Lan、Qiuling Song
DOI:10.1039/c8cc05390a
日期:——
Herein, we report an efficient and practical strategy for the synthesis of five types of imidazo[2,1-a]isoquinolines via Cp*RhIII-catalyzed [4+2] annulation of 2-arylimidazoles and α-diazoketoesters, whose structural and substituted diversity at 5- or 6-position can be precisely controlled by the α-diazoketoester coupling partners. Compared with previous reports, in this study, we merged two attractive
本文中,我们报告了通过Cp * Rh III催化的2-芳基咪唑和α-重氮酮酸酯的[4 + 2]环合反应合成五种咪唑并[ 2,1- a ]异喹啉的有效而实用的策略。可以通过α-重氮酮酸酯偶合伙伴精确控制5位或6位取代的多样性。与以前的报告相比,在这项研究中,我们通过选择合适的酯基团(–COOEt,–COO tBu或–COOiPr)或廉价的添加剂(HOAc或KOAc)。此外,通过几种生物活性化合物的简明合成和代表性药物的后期修饰,证明了这些方法的合成功效。
C-N Bond Formation Catalyzed by Ruthenium Nanoparticles Supported on N-Doped Carbon via Acceptorless Dehydrogenation to Secondary Amines, Imines, Benzimidazoles and Quinoxalines
作者:Bin Guo、Hong-Xi Li、Shi-Qi Zhang、David James Young、Jian-Ping Lang
DOI:10.1002/cctc.201801525
日期:2018.12.21
Ruthenium nanoparticles (NPs) supported on N‐doped carbon (Ru/N−C) were prepared by the pyrolysis of cis‐Ru(phen)2Cl2 loaded onto carbon powder (VULCAN XC72R) at 800 °C. Ru/N−C NPs (0.2 mol% Ru) selectively catalyzed either acceptorless dehydrogenation coupling (ADC) or auto‐transfer‐hydrogen (ATH) reactions of amines with alcohols to imines and secondary amines. Such selectivity could be controlled
Novel molecular iodine catalyzed cyclization reactions of 2-amino anilines with aryl alkyl ketones under oxidant and metal-free conditions are described. The reaction likely involves sequential C–N bond formation followed by C(CO)–C(alkyl) bondcleavage. Various 2-substituted benzimidazoles are obtained in moderate to good yields in a single step from readily available acetophenones, propiophenones