1383791-22-7Relevant academic research and scientific papers
Electrophilic cyclization of N-alkynyl-2-(organochalcogen)imidazoles: An alternative access to imidazo[2,1-b]chalcogenazoles
Grimaldi, Tamiris B.,Godoi, Benhur,Roehrs, Juliano A.,Speranca, Adriane,Zeni, Gilson
supporting information, p. 2646 - 2652 (2013/06/05)
We present here a practical synthesis of multifunctional imidazo[2,1-b]chalcogenazoles through electrophilic cyclization of N-alkynyl-2-(organochalcogen)imidazoles. The cyclization reaction proceeded cleanly and smoothly under mild reaction conditions in the presence of air. The methodology was highly regioselective: In a competition between the chalcogen and oxygen atoms, only S-, and Se-heterocycles were obtained. The resulting imidazo[2,1-b]chalcogenazoles proved to be versatile as precursors for the synthesis of more highly functionalized imidazoselenazoles through copper-catalyzed cross-coupling reactions with arene- and alkanethiols, leading to Ullmann-type products in good yields. We present here a practical synthesis of multifunctional imidazo[2,1-b]chalcogenazoles through electrophilic cyclization of N-alkynyl-2-(organochalcogen)imidazoles. The methodology was highly regioselective: In a competition between the chalcogen and oxygen atoms, only S- and Se-heterocycles were obtained. The resulting imidazo[2,1-b] chalcogenazoles proved to be versatile as precursors for the synthesis of more highly functionalized imidazoselenazoles. Copyright
Three-step one-pot synthesis of imidazo[2,1-b]chalcogenazoles via intramolecular cyclization of N-alkynylimidazoles
Roehrs, Juliano Alex,Pistoia, Renan P.,Back, Davi F.,Zeni, Gilson
supporting information; experimental part, p. 1791 - 1796 (2012/07/31)
Imidazo-chalcogenazoles are easily accessible from the corresponding N-alkynylimidazoles by a three-step, one-pot chalcogenation reaction. The generality of this reaction has been established with various substituted N-alkynylimidazoles as well as elemental chalcogens. By accessing the key intermediate 2-chalcogenolate-N-alkynylimidazole it was also possible to prepare dichalcogenide derivatives. Copyright
