Homocoupling of bromotriazole derivatives on metal complex catalysts

General Method of Synthesis of 5-(Het)arylamino-1,2,3-triazoles via Buchwald–Hartwig Reaction of 5-Amino- or 5-Halo-1,2,3-triazoles

“…All reagents were used as purchased from Sigma-Aldrich (Munich, Germany). In the study, 1,4-disubstituted-5-chloro- [ 48 ] and 5-amino-1,2,3-triazoles [ 47 ] and 1-benzyl-4-bromo-5-methyl-1 H -1,2,3-triazole [ 56 ] were synthesized according to published procedures. (THP-Dipp)Pd(cinn)Cl [ 57 ], (THP-Dipp)Pd(allyl)Cl [ 58 ] and (THP-Dipp)Pd(metallyl)Cl were synthesized according to published procedure [ 57 ] from corresponding NHC-silver (I) complexes.…”

Homocoupling Reactions of Azoles and Their Applications in Coordination Chemistry

“…A handful of papers [ 22 , 23 ] have used the tactical placement of heteroatoms for the coordination of metals in the activation of specific C–H bonds. Other papers [ 24 , 25 ] utilize the possibility of the oxidative addition of Pd into a carbon halogen bond to form di-azole Pd complexes, which can undergo reductive elimination to form desired intermolecular homocoupled products.…”

“…Afanas’ev et al reported a method for the homocoupling of 4-bromo-1,2,3-triazoles to access the corresponding 4,4′-bistriazoles in quantitative yields [ 24 ]. The intermolecular homocoupling was achieved by mixing 4-brominated triazoles with 1.0 mol% Pd(OAc) 2 , in the presence of additives (pinB) 2 , SPhos and KOH.…”

“…The homocoupling between 4-bromotriazoles has been reported by Afanas´ev et al using in situ generated Ni 0 as a catalyst ( Scheme 14 ) [ 24 ]. The homocoupling functions via an in situ formation of Ni 0 (PPh 3 ) 4 from NiCl 2 and Zn 0 , which undergoes oxidative addition of two equivalents of 4-bromotriazoles, followed by a reductive elimination to form the desired homocoupled products ( Scheme 14 b).…”