Yield:603301-13-9 81%

Reaction Conditions:

in butan-1-ol;Heating / reflux;

Steps:

8

PREPARATION 8; 5-Bromoimidazo [1, 2-a] pyridine; Add 2-bromo-I, l-diethoxyethane (3.64 g, 18.48 mmol) to a solution of 6- bromopyridin-2-ylamine (l. Og, 5.77 mmol) in n-butanol (40 ml). Reflux overnight and cool. Filtration of the reaction mixture gives 1.3 g (81%) of 5-bromoimidazo [1, 2- pyridine hydrobromide as a white solid. ESMS (M++1) : 198.9 m/z. Add saturated sodium bicarbonate (300 ml) to a suspension of 5- bromoimidazo [1, 2-a] pyridine hydrobromide (13. 0g, 46.96 mmol) in ethyl acetate. Separate the organic layer, wash with saturated sodium bicarbonate, dry over magnesium sulfate, and concentrate under reduced pressure to give 9.7 g (100%) of the title compound as a white solid.

References:

WO2003/76398,2003,A2 Location in patent:Page/Page column 20