Net Rearrangements of 4-acetyl-3-(4-substituted phenylamino)-2-(5-nitropyridin-2-yl)isoxazol-5(2H)-ones to Imidazo [1, 2-a]pyridines by Flash-Vacuum-Pyrolysis (F.V.P))

4-acetyl-3-(4-substituted phenylamino)-2-(5-nitropyridin-2-yl) isoxazol-5(2H)-ones, rearranged under Flash-Vacuum-Pyrolysis (F.V.P) conditions accompanied by elimination of carbon dioxide to give imidazo[1, 2-a]pyridines in high to excellent yields (90-95%).

Isoxazolones, Imidazopyridines, Flash-Vacuum-Pyrolysis.