2-Hydrazinopyridine → 3-(2-Bromo-3-methylphenyl)-[1,2,4]triazolo[4,3-a]pyridine

Participants

Reaction Conditions

Reaction Steps

A solution of 2-hydrazinopyridine, 97% (0.254 g, 2.325 mmol), 2-bromo-3-methylbenzoic acid (0.50 g, 2.325 mmol), benzotriazol-1-yl-oxytripyrrolidinophosphonium hexafluorophosphate (PyBOP, 1.452 g, 2.79 mmol), and DIEA (0.812 mL, 4.65 mmol) in DCM (6 mL) was stirred at RT until starting material was completely consumed (˜3 h). The mixture was concentrated and chromatographed on silica gel using 0-5% MeOH/DCM to afford a light yellow foam which was dissolved in CH3CN followed by the addition of Lawesson's reagent (0.470 g, 1.163 mmol) and heated at 80° C. for 17 h. The mixture was concentrated and chromatographed on silica gel using 25% EtOAc/hexanes and 0-5% MeOH/DCM to afford a yellow oil as 3-(2-bromo-3-methylphenyl)-[1,2,4]triazolo[4,3-a]pyridine.

Provenance & Evidence