Tetrahydrofuran → 5-Bromo-2-iodobenzaldehyde

Participants

Reaction Steps

5-bromo-2-iodobenzonitrile (25.2 g, 81.8 mmol) in tetrahydrofuran (140 mL) was cooled to −78° C. and diisobutylaluminum hydride (1.0M in hexanes; 115 mL, 115 mmol) over 10 minutes, and the reaction was allowed to warm to room temperature and left stirring overnight. Analytical LCMS indicated consumption of starting material so the mixture was carefully quenched with ethyl acetate and methanol. After 1.5 hours the solution was concentrated then diluted with dichloromethane. 1N Aqueous hydrochloric acid was added and a precipitate formed as the reaction was stirred vigorously for 1 hour. The precipitate was filtered off and the filtrate was evaporated then triturated with dichloromethane and hexanes, which caused more precipitate to form. The mixture was filtered and the organic portions were set aside while the combined precipitates were suspended in tetrahydrofuran and 6N hydrochloric acid (aqueous). The reaction was stirred vigorously for 1 hour at which point analytical TLC indicated complete formation of the product. The reaction was extracted with dichloromethane and combined with the previous organic portions. The mixture was dried over magnesium sulfate then filtered, evaporated, and purified by silica gel chromatography (0-15% dichloromethane in hexanes) to yield the title compound.

Provenance & Evidence