Hydrogen Peroxide → Methyl 4-bromopicolinate

A solution of 4-bromopyridine hydrochloride (595 mg, 3.06 mmol) in DCM (20 mL) is washed with aqueous NaHCO3 (2×20 mL), dried (MgSO4) and filtered. The filtrate is made up to 45 mL by the addition of more DCM, then water (3 mL) is added, followed by iron(II) sulphate heptahydrate (8.51 g, 30.6 mmol) and conc. H2SO4 (0.95 mL, 9.18 mmol). In a separate flask, methyl pyruvate (4.15 mL, 46 mmol) is treated with hydrogen peroxide (3.5 mL, 30.6 mmol, 30% solution in water) at −10° C., then this solution is added to the DCM/water mixture at −10° C. with vigorous stirring. After 15 minutes, the reaction is diluted with iced water (100 mL) and extracted into DCM (4×20 mL). The combined DCM phases are dried (MgSO4) and removed in vacuo. The title compound is obtained after sequential column chromatography (gradient elution—10-40% EtOAc in heptane with 0.5% triethylamine, then repeating with 0-20% EtOAc in heptane with 0.5% triethylamine).

1. dry with materialdried (MgSO4)
2. filtrationfiltered
3. additionThe filtrate is made up to 45 mL by the addition of more DCM
4. additionwater (3 mL) is added
5. extractionextracted into DCM (4×20 mL)
6. dry with materialThe combined DCM phases are dried (MgSO4)
7. customremoved in vacuo

ORD record

ord-e12a56ca38cd4e458bf904ad5142ad2f

Source dataset

uspto-grants-2012_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08273747B2