23501-93-1

619-22-7

General procedure for the synthesis of m-dimethylaminobenzaldehyde from 3-(dimethylamino)benzyl alcohol: commercially available 3-(dimethylamino)benzyl alcohol (750 mg, 5 mmol) was dissolved in a solvent mixture of dichloromethane (DCM) and dimethyl sulfoxide (DMSO). To this solution, triethylamine (Et3N, 2.8 mL, 20 mmol) and sulfur trioxide-pyridine complex (SO3-Py, 1.59 g, 10 mmol) were added sequentially. The reaction mixture was stirred for 2 h at room temperature. After completion of the reaction, dichloromethane was removed by distillation under reduced pressure. Saturated aqueous ammonium chloride (NH4Cl) was added to the residue, which was then extracted with ethyl acetate (EtOAc). The organic phase was washed with water, dried over anhydrous magnesium sulfate (MgSO4) and concentrated under reduced pressure. The crude product was purified by column chromatography (eluent ratio: ethyl acetate/hexane = 1/2) to afford m-dimethylaminobenzaldehyde (670 mg, 90% yield). Mass spectrometry analysis showed [M+H]+ = 150.