827-43-0Relevant articles and documents
Base-promoted annulation of amidoximes with alkynes: Simple access to 2,4-disubstituted imidazoles
Hua, Ruimao,Iqbal, Muhammad Asif,Lu, Le,Mehmood, Hina
, (2020/09/17)
An efficient construction of imidazole ring by a Cs2CO3-promoied annulation of amidoximes with terminal alkynes in DMSO has been developed. This protocol provides a simple synehetic ropte with high atom-utilieation for the synthesis of 2,4-disubstituted imidazoles in good yields under transition-metal-free and ligand-free conditions. Intornal alkynes can also undetgo the annulation to give 2,4,5-trisubstituted imidazoles.
Synthesis of Imidazoles and Pyrimidines Using Palladium-Catalyzed Decarboxylative Intramolecular Condensation of 1,2,4-Oxadiazol-5(4 H)-ones
Shimbayashi, Takuya,Okamoto, Kazuhiro,Ohe, Kouichi
, p. 1916 - 1920 (2014/08/18)
We found that 1,2,4-oxadiazol-5(4H)-ones acted as iminonitrene equivalents in the presence of a palladium catalyst and a stoichiometric amount of phosphine and that aza-Wittig-type condensation with the internal carbonyl moiety occurred to afford the corresponding imidazoles and pyrimidines. Georg Thieme Verlag Stuttgart. New York.
Atom-economical synthesis of N-heterocycles via cascade inter-/intramolecular C-N Bond-forming reactions catalyzed by Ti amides
Shen, Hao,Xie, Zuowei
supporting information; experimental part, p. 11473 - 11480 (2010/10/02)
Direct and efficient catalytic reactions with excellent regioselectivity for the preparation of a series of substituted isoindoles, isoquinolines, and imidazoles are reported. Reaction of C6H4(2-CN)C≡C-R with an array of amines, catalyzed by 10 mol % of [σ:η1: η5-(OCH2)(Me2NCH2)C 2B9H9]Ti(NMe2) (1), gives a series of substituted isoindoles in very high yields. In a similar manner, interaction of C6H4(2-CH2CN)C≡C-Ph with various kinds of amines affords a wide range of substituted isoquinolines. On the other hand, treatment of propargylamines (R′C≡CCH2NHR′′) with nitriles in the presence of 10 mol % of 1 produces a class of substituted imidazoles in high yields. A possible reaction mechanism is proposed, involving sequential inter- and intramolecular C-N bond formation via hydroamination/ cyclization reaction of cyanoalkynes with amines or nitriles with propargylamines catalyzed by titanium amides.