1,2,3-Triazolylidene palladium complex with triazole ligand: Synthesis, characterization and application in Suzuki-Miyaura coupling reaction in water

Palladium complex containing 1,2,3-triazolylidene and a labile triazole moiety has been prepared and characterized. Simple azide alkyne click reaction using three fold excess of dibromoethane afforded 1(2-bromoethyl)-4-phenyl-1H-1,2,3-triazole. The latter on dehydrobromination yields N-vinyl triazole (N-tzl) which is subsequently used for preparing its triazolium salt. Further, N-tzl-Pd-N-tzl complex was prepared from triazole by simple palladation which underwent a ligand substitution reaction when treated with in situ generated triazolylidene to form C-tzl-Pd-N-tzl type complex. This mixed palladium complex was found to be highly effective in catalyzing Suzuki-Miyaura coupling reaction between aryl halides and aryl boronic acids in water at room temperature with very low catalyst loading. (C) 2018 Elsevier Ltd. All rights reserved.