Facile synthesis of 3,5-diaryl-1,2,4-triazoles via copper-catalyzed domino nucleophilic substitution/oxidative cyclization using amidines or imidates as substrates

Publikations-Art

Zeitschriftenbeitrag (peer-reviewed)

Autoren

Sudheendran, K; Schmidt, D.; Frey, W.; Conrad, J.; Beifuss, U.

Erscheinungsjahr

2014

Veröffentlicht in

Tetrahedron

Band/Volume

70/

DOI

10.1016/j.tet.2014.01.019

Seite (von - bis)

1635-1645

Two methods for the synthesis of 3,5-diaryl-1,2,4-triazoles, both domino reactions, are reported. The first procedure, the Cu(OTf)₂-catalyzed reaction between two amidines using NaHCO₃ as a base, 1,10-phenanthroline as an additive and K₃[Fe(CN)₆]/ atmospheric oxygen as the oxidant, delivers 3,5-diaryl-1,2,4-triazoles with yields up to 68%. The second procedure for the synthesis of 3,5-diaryl-1,2,4- triazoles with yields up to 64% rests on the Cu(OTf)₂-catalyzed reaction between two imidates and ammonium carbonate. This method features the formation of three bonds in a single synthetic step.