p-Toluenesulfonic acid → 1-(2-fluoro-5-methoxy-4-((6-methoxypyridin-3-yl)methoxy)benzyl)-5-iodo-1H-benzo[d]imidazole

Participants

Reaction Steps

To a stirred solution of N1-(2-fluoro-5-methoxy-4-((6-methoxypyridin-3-yl)methoxy)benzyl)-4-iodobenzene-1,2-diamine (0.36 g, 0.70 mmol) in ethanol (10 mL) was added triethyl orthformate (0.31 g, 2.11 mmol) and p-toluenesulfonic acid (0.007 g, 0.035 mmol). The reaction mixture was heated to reflux. After 30 min, the brown solution was allowed to cool to room temperature and was concentrated. The residue was partitioned between water and dichloromethane. The phases were separated, and the aqueous phase extracted with dichloromethane. The combined organic phases were washed with water and brine, dried over magnesium sulfate, filtered, and concentrated. Chromatographic purification (Combi-Flash, 12 g SiO2 column, 1-5% methanol/dichloromethane elute) afforded 0.25 g (68%) of 1-(2-fluoro-5-methoxy-4-((6-methoxypyridin-3-yl)methoxy)benzyl)-5-iodo-1H-benzo[d]imidazole as a tan solid.

Provenance & Evidence