152278-31-4Relevant articles and documents
Preparation of 1,2,5-Trisubstituted 1H-Imidazoles from Ketenimines and Propargylic Amines by Silver-Catalyzed or Iodine-Promoted Electrophilic Cyclization Reaction of Alkynes
Zhou, Xiaorong,Jiang, Zheng,Xue, Lexing,Lu, Ping,Wang, Yanguang
, p. 5789 - 5797 (2015/09/15)
From readily available propargylic amines, 1,2,5-trisubstituted imidazoles are efficiently obtained through a cascade reaction catalyzed by AgOTf or promoted by molecular iodine. The AgOTf-catalyzed reaction involves nucleophilic addition of propargylic amine to ketenimine, a silver-catalyzed electrophilic cyclization reaction of alkyne, and a tautomerism/isomerism/metal-H exchange cascade. The iodine-mediated counterpart yields 5-formyl-1,2-disubtituted imidazoles, which presumably includes a cascade hydrolysis/oxidation reaction. Furthermore, the presented protocol can be scaled up and the resultant 1,2,5-trisubstituted imidazole can be converted into fused indeno[1,2-d]imidazole. 1,2,5-Trisubstituted imidazoles are efficiently prepared from readily available propargylic amines through a AgOTf-catalyzed or molecular iodine-promoted cascade reaction. The presented protocol can be scaled up and the resultant 1,2,5-trisubstituted imidazoles can be converted into fused indeno[1,2-d]imidazoles.
