Dipyrazolo[1,5-a:4',3'-c]pyridines - a new heterocyclic system accessed via multicomponent reaction.
The synthesis of dipyrazolo[1,5-a:4',3'-c]pyridines is described. Easily obtainable 5-alkynylpyrazole-4-carbaldehydes, p-toluenesulfonyl hydrazide, and an aldehyde or ketone containing an α-hydrogen atom were reacted in a silver triflate catalyzed multicomponent reaction affording new tricyclic compounds with a dipyrazolo[1,5-a:4',3'-c]pyridine core. Detailed NMR spectroscopic investigations ((1)H, (13)C and (15)N) were undertaken with all obtained compounds.
Department of Drug and Natural Product Synthesis, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria.
Wolfgang
W
Holzer
Gytė
G
Vilkauskaitė
Eglė
E
Arbačiauskienė
Algirdas
A
Sačkus
NMR spectroscopy; cyclization; multicomponent reaction; nitrogen heterocycles; pyrazole