Bromobenzene → Methyl 4-(4-bromophenyl)-4-oxobutanoate

To a stirred suspension of anhydrous aluminum chloride (26.9 g, 0.202 mol) in dichloromethane (415 mL) at 5° C. under nitrogen was added dropwise neat bromobenzene (10.0 mL, 0.0950 mol), and the mixture was stirred briefly. To the mixture was added dropwise a solution of 3-carbomethoxypropionyl chloride (12.9 mL, 0.105 mol) in dichloromethane (200 mL) over 70 minutes, and the mixture was allowed to slowly warm to room temperature. After 4 days, the mixture was recooled to 5° C. and quenched with the dropwise addition of water (600 mL). The organics were washed with additional water (200 mL), aqueous sodium bicarbonate, water, and brine. The organics were dried (Na2SO4), and rotary evaporated to an oil, which crystallized. The residue was dissolved in chloroform, and the solution was purified by chromatography on silica gel (435 g, 230-400 mesh), eluting with hexanes-acetone (9:1, 10×400 mL; 8:1, 7×400 mL),to give 21.2 g of 4-(4-bromo-phenyl)-4-oxo-butyric acid, methyl ester as an off-white solid; mp 49-51° C.

1. customwas recooled to 5° C.
2. customquenched with the dropwise addition of water (600 mL)
3. washThe organics were washed with additional water (200 mL), aqueous sodium bicarbonate, water, and brine
4. dry with materialThe organics were dried (Na2SO4)
5. customrotary evaporated to an oil, which
6. customcrystallized
7. dissolutionThe residue was dissolved in chloroform
8. customthe solution was purified by chromatography on silica gel (435 g, 230-400 mesh)
9. washeluting with hexanes-acetone (9:1, 10×400 mL; 8:1, 7×400 mL)

ORD record

ord-00217cd7bb13447fb55c6c03b2b20d83

Source dataset

uspto-grants-2002_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06399612B1