Dimethyl Sulfate → 5-Bromo-2-chloro-3,4-dimethoxybenzaldehyde

Participants

Reaction Conditions

Reaction Steps

To the mixture of aldehyde 156 (15.0 g, 56.5 mmol) in THF (300 mL) were added dimethylsulfate (7.0 mL, 73.5 mmol) and LiOH monohydrate (3.1 g, 73.5 mmol). The mixture was stirred for 3 hours at 65° C. The mixture was cooled to r.t. and filtered to remove insoluble materials through celite. The filtrate was extracted with EtOAc/aq. 50% NaCl solution (200 mL/500 mL). The organic layer was dried over MgSO4, filtered, and concentrated in vacuo. The residue was purified by silica gel column chromatography to provide the compound 157 (11.1 g, 70%).

Provenance & Evidence