Bromine → Methyl 4-bromo-3-oxopentanoate

A solution of bromine (28.3 g, 0.177 mol) in chloroform (30 mL) was added dropwise over 2 h to a solution of methyl propionylacetate (23.5 g, 0.177 mol) in chloroform (155 mL) at 0-5° C. The mixture was stirred for 30 min, and the cooling bath was removed. The mixture was stirred for 18 h, and ice water (200 mL) was added. The organic layer was collected and washed with cold water (2×200 mL), 10% aqueous sodium thiosulfate (2×200 mL) and brine (200 mL). The filtered solution was dried (Na2SO4) and concentrated to 36.5 g of the title compound as a clear liquid.

1. customthe cooling bath was removed
2. stirringThe mixture was stirred for 18 h
3. additionice water (200 mL) was added
4. customThe organic layer was collected
5. washwashed with cold water (2×200 mL), 10% aqueous sodium thiosulfate (2×200 mL) and brine (200 mL)
6. dry with materialThe filtered solution was dried (Na2SO4)
7. concentrationconcentrated to 36.5 g of the title compound as a clear liquid

ORD record

ord-8c52407f30ee42c992fd7a73c64156fc

Source dataset

uspto-grants-2007_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07282501B2