Diisobutylaluminum hydride → 4-Bromo-2,6-dimethylbenzaldehyde

DIBAL-H (1.0M in hexanes; 22.0 mL, 22.0 mmol) was added to a solution of 4-bromo-2,6-dimethylbenzonitrile (3.87 g, 18 mmol) in CH2Cl2 (50 mL) at 0° C., and the resulting mixture stirred at 25° C. for 3 h. Saturated aqueous sodium potassium tartrate solution (75 mL) was then slowly added, and the resulting mixture was stirred vigorously for 30 min. The organic layer was separated, and the aqueous layer was extracted with CH2Cl2). The combined organic extracts were dried over MgSO4, filtered, and concentrated in vacuo. Chromatographic purification of the residue (silica gel, 0-20% EtOAc/hexanes) furnished 4-bromo-2,6-dimethylbenzaldehyde as a light brown solid.