Ethanol → (Z)-ethyl 3-(5-bromo-2-methoxy-3-nitropyridin-4-yl)-2-hydroxyacrylate

HRID 930871Notes

Reaction equation

C(O)C.[Br:4][C:5]1[C:6]([CH3:16])=[C:7]([N+:13]([O-:15])=[O:14])[C:8]([O:11][CH3:12])=[N:9][CH:10]=1.[C:17](OCC)(=[O:23])[C:18]([O:20][CH2:21][CH3:22])=[O:19].[O-]CC.[K+]>C(OCC)(=O)C.CCOCC>[Br:4][C:5]1[C:6](/[CH:16]=[C:17](\[OH:23])/[C:18]([O:20][CH2:21][CH3:22])=[O:19])=[C:7]([N+:13]([O-:15])=[O:14])[C:8]([O:11][CH3:12])=[N:9][CH:10]=1

Participants

Conditions

Temperature: 45 °C

Procedure

To a solution of ethanol (15 mL) and ether (150 mL) were added 5-bromo-2-methoxy-4-methyl-3-nitropyridine (14.82 g, 60 mmol), diethyl oxalate (13.15 g, 90 mmol), and potassium ethoxide (6.06 g, 72 mmol). The reaction mixture was heated at 45° C. for 24 hours. During the reaction, the flask was shaken by hand several times. After cooling, the reaction mixture was partitioned between water and ethyl acetate. The aqueous layer was extracted with additional ethyl acetate three times. The combined organic layers were washed with brine, dried over MgSO4, filtered, and concentrated. The residue was purified by flash chromatography on silica gel eluting with 10-20% ethyl acetate in hexanes to 9.5 g of the title compound (yield 46%).

Workup

customDuring the reaction
temperatureAfter cooling
customthe reaction mixture was partitioned between water and ethyl acetate
extractionThe aqueous layer was extracted with additional ethyl acetate three times
washThe combined organic layers were washed with brine
dry with materialdried over MgSO4
filtrationfiltered
concentrationconcentrated

Sources & evidence

ORD record: ord-de2d6aa03c4042f680d3eb0a7009f046
Source dataset: uspto-grants-2016_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US09296741B2

Reaction notes

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