IMidazo[1,2-a]pyridine-3-carboxiMidaMide, 6-fluoro- synthesis

Yield:1220039-94-0 81%

Reaction Conditions:

Stage #1: 6-fluoroimidazo[1,2-a]pyridine-3-carbonitrilewith sodium methylate in methanol at 20; for 72 h;
Stage #2: with ammonium chloride in methanol; for 24 h;Reflux;

Steps:

25.b

b) 6-Fluoroimidazo[1,2-a]pyridine-3-carboximidamide Sodium methoxide (0.53 g, 9.87 mmol) was added to a stirred suspension of 6-fluoroimidazo[1,2-a]pyridine-3-carbonitrile (Preparation 25a, 15.9 g, 98.67 mmol) in methanol (200 mL) and the resulting mixture was stirred at room temperature for 3 days. Ammonium chloride (5.8 g, 108.5 mmol) was added and the mixture was heated to reflux and stirred for 24 hours. The solvent was evaporated and the resulting solid was triturated with ethyl acetate to give the title compound (14.3 g, 81%) as a brown solid. LRMS (m/z): 179 (M+1)⁺.1H NMR (300 MHz, DMSO-d₆) δ ppm 7.68 (m , 1H), 7.87 (dd, 1H), 8.33 (s, 1H), 8.87 (m, 1H).

References:

EP2397482,2011,A1 Location in patent:Page/Page column 48