反应详情

To a solution of calcium chloride (46.5 kg) in ethanol (336 L) were added tetrahydrofuran (672 L) and methyl 4-bromo-3,5-dimethoxybenzoate (96.0 kg) to obtain a suspension. To the suspension was added sodium borohydride (31.7 kg) by portions at room temperature, and the mixture was stirred for about 9 hours at temperature of room temperature to 45° C. The reaction mixture was added dropwise to aqueous HCl solution and stirred for about 16 hours at room temperature. Organic solvent was removed in vacuo, and water (1440 L) was added to the residue and stirred for 1 hour at 50° C. After cooling, the crystalline precipitates were collected by filtration and dried to yield 4-bromo-3,5-dimethoxybenzyl alcohol (83.3 kg) as colorless crystals.

1. customto obtain a suspension
2. stirringstirred for about 16 hours at room temperature
3. customOrganic solvent was removed in vacuo, and water (1440 L)
4. additionwas added to the residue
5. stirringstirred for 1 hour at 50° C
6. temperatureAfter cooling
7. customthe crystalline precipitates
8. filtrationwere collected by filtration
9. customdried