Metal-free 5-exo-dig cyclization of propargyl urea using TBAF
摘要:
We present the first results of the intramolecular cyclization of propargyl ureas catalyzed by TBAF. Depending on the substituents close to the triple bond, imidazolone or methylene-imidazolidinone was obtained. The dual activation of the triple bond by interaction with TBAF via the cation-pi is thought to be responsible. (C) 2014 Elsevier Ltd. All rights reserved.
Tetrasubstituted 2-Imidazolones via Ag(I)-Catalyzed Cycloisomerization of Propargylic Ureas
作者:Vsevolod A. Peshkov、Olga P. Pereshivko、Sweta Sharma、Thirumal Meganathan、Virinder S. Parmar、Denis S. Ermolat’ev、Erik V. Van der Eycken
DOI:10.1021/jo200789t
日期:2011.7.15
A one-pot protocol based on a Ag(I)-catalyzed cycloisomerization of propargylic ureas, derived from secondary propargylamines and isocyanates, was developed for the generation of the 2-imidazolone core.
We present the first results of the intramolecular cyclization of propargyl ureas catalyzed by TBAF. Depending on the substituents close to the triple bond, imidazolone or methylene-imidazolidinone was obtained. The dual activation of the triple bond by interaction with TBAF via the cation-pi is thought to be responsible. (C) 2014 Elsevier Ltd. All rights reserved.