6528-83-2Relevant articles and documents
An Unexpected Formation of 2-Arylbenzimidazoles from α,α-Diiodo-α’-acetoxyketones and o-Phenylenediamines
Sadhukhan, Santu,Mondal, Swagata,Baire, Beeraiah
, (2022/03/01)
An unusual reactivity of the α,α-diiodo-α’-acetoxyketones with o-phenylenediamines is reported through the formation of 2-arylbenzimidazoles. A systematic study through a series of fruitful control experiments and isolation of key intermediates unravelled the unprecedented domino mechanism. This process involves a stepwise two-carbon fragmentation pathway through domino and sequential amidation–aziridination–decarbonylation–I2-mediated aminative cyclization–oxidation reactions. This strategy employs no additives like oxidant, metal catalyst, bases, and represents yet another novel reactivity profile of the building blocks α,α-diiodo-α’-acetoxyketones.
Selective C-C bonds formation, N-alkylation and benzo[d]imidazoles synthesis by a recyclable zinc composite
Zhu, Guanxin,Duan, Zheng-Chao,Zhu, Haiyan,Ye, Dongdong,Wang, Dawei
supporting information, p. 266 - 270 (2021/08/06)
Earth abundant metals are much less expensive, promising, valuable metals and could be served as catalysts for the borrowing hydrogen reaction, dehydrogenation and heterocycles synthesis, instead of noble metals. The uniformly dispersed zinc composites were designed, synthesized and carefully characterized by means of XPS, EDS, TEM and XRD. The resulting zinc composite showed good catalytic activity for the N-alkylation of amines with amines, ketones with alcohols in water under base-free conditions, while unsaturated carbonyl compounds could also be synthesized by tuning the reaction conditions. Importantly, it was the first time to realize the synthesis of 2-aryl-1H-benzo[d]imidazole derivatives by using this zinc composite under green conditions. Meanwhile, this zinc catalyst could be easily recovered and reused for at least five times.
Visible-Light Photoredox Catalyzed Double C-H Functionalization: Radical Cascade Cyclization of Ethers with Benzimidazole-Based Cyanamides
Jiang, Si,Tian, Xiao-Jing,Feng, Shu-Yao,Li, Jiang-Sheng,Li, Zhi-Wei,Lu, Cui-Hong,Li, Chao-Jun,Liu, Wei-Dong
supporting information, p. 692 - 696 (2021/02/01)
A visible-light photoredox catalyzed radical cascade cyclization of simple ethers with cyanamides is developed at room temperature. This strategy involves sequential inert Csp3-H/Csp2-H functionalizations through intermolecular addition reaction of oxyalkyl radicals to N-cyano groups followed by radical cyclization of iminyl radicals in situ generated with C-2 aryl rings. This method allows for efficient synthesis of tetracyclic benzo[4,5]imidazo[1,2-c]quinazolines. Importantly, this is the first example of an intermolecular-intramolecular radical cascade cyclization reaction of cyanamides.
