e.g. Filippa Pettersson or Cancer Res. 75(6) , 1102-12, (2015) or 10.1002/anie.201600521
Palladium-catalyzed chemoselective monoarylation of hydrazides for the synthesis of [1, 2, 4] triazolo [4, 3-a] pyridines
…, OR Thiel, MM Achmatowicz, RD Larsen, D Zhang
Index: Reichelt, Andreas; Falsey, James R.; Rzasa, Robert M.; Thiel, Oliver R.; Achmatowicz, Michal M.; Larsen, Robert D.; Zhang, Dawei Organic Letters, 2010 , vol. 12, # 4 p. 792 - 795
An efficient and convenient method for the synthesis of [1, 2, 4] triazolo [4, 3-a] pyridines was exemplified by the synthesis of 20 analogues bearing a variety of substituents at the 3- position. The methodology involves a palladium-catalyzed addition of hydrazides to 2- chloropyridine, which occurs chemoselectively at the terminal nitrogen atom of the hydrazide, followed by dehydration in acetic acid under microwave irradiation.