Copper-free Sonogashira cross-coupling reaction catalyzed by polymer-supported N-heterocyclic carbene palladium complex

• Published in: Tetrahedron letters Vol. 48; no. 40; pp. 7079 - 7084
• Main Authors: Kim, Jong-Ho, Lee, Dong-Ho, Jun, Bong-Hyun, Lee, Yoon-Sik
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 01.10.2007; Elsevier
• Subjects: Chemistry; Chemistry, Organic; Copper-free; Heterogeneous catalysis; N-Heterocyclic carbene (NHC); Palladium (Pd); Physical Sciences; Polymer-supported catalyst; Science & Technology; Sonogashira reaction; Heterogeneous catalysis; Palladium (Pd); Sonogashira reaction; N-Heterocyclic carbene (NHC); Polymer-supported catalyst; Copper-free; heterogeneous catalysis; polymer-supported catalyst; copper-free; sonogashira reaction; TERMINAL ALKYNES; ARYL BROMIDES; IODIDES; palladium (Pd); AMINE-FREE; N-heterocyclic carbene (NHC); CHEMISTRY; LIGAND; EFFICIENT; WATER
• ISSN: 0040-4039; 1873-3581
• DOI: 10.1016/j.tetlet.2007.08.015

A core-shell type of polymer-supported N-heterocyclic carbene (NHC) palladium catalyst was applied to Sonogashira cross-coupling reactions without copper cocatalyst under ambient atmosphere. This supported NHC–palladium complex efficiently catalyzed the copper-free Sonogashira reaction of various aryl iodides and bromides with terminal alkynes; the reaction exhibited high dependency on the temperature and the amount of base as well as its nature. In addition, this heterogeneous catalyst exhibited good reusability for the copper-free Sonogashira reaction.