Solvent-free copper-catalyzed click chemistry for the synthesis of N-heterocyclic hybrids based on quinoline and 1,2,3-triazole

• DOI: 10.3762/bjoc.13.232
• Publication Date: 2017-11-06T09:58:13Z
• Authors: Martina Tireli; Silvija Maračić; Stipe Lukin; Marina Juribašić ...; Dijana Žilić; Mario Cetina; Ivan Halasz; Silvana Raić-Malić; Krunoslav Užarević
• Keywords: Quinoline; Triazole; Moiety; 1,2,3-Triazole

Copper-catalyzed mechanochemical click reactions using Cu(II), Cu(I) and Cu(0) catalysts have been successfully implemented to provide novel 6-phenyl-2-(trifluoromethyl)quinolines with a phenyl-1,2,3-triazole moiety at O-4 of the quinoline core. Milling procedures proved be significantly more efficient than corresponding solution reactions, up 15-fold gain in yield. Efficiency both milling depended on p-substituent azide reactant, resulting H < Cl Br I reactivity bias. Solid-state catalysis Cu(II) entailed direct involvement copper species reaction generation highly luminescent compounds which hindered situ monitoring by Raman spectroscopy. However, processes was enabled form brass media offered insight into pathway CuAAC indicating that is most likely conducted surface balls. Electron spin resonance spectroscopy used determine oxidation states respective bulk products obtained procedures.