Sulfuric Acid → Methyl 2-bromo-4-fluoro-5-nitrophenoxyformate

HRID 1805142Notes

Reaction equation

HRID 1805142 reaction equation
[C:1](=[O:13])([O:11][CH3:12])[O:2][C:3]1[CH:8]=[CH:7][C:6]([F:9])=[CH:5][C:4]=1[Br:10].OS(O)(=O)=O.[N+:19]([O-])([O-:21])=[O:20].[K+]>>[C:1](=[O:13])([O:11][CH3:12])[O:2][C:3]1[CH:8]=[C:7]([N+:19]([O-:21])=[O:20])[C:6]([F:9])=[CH:5][C:4]=1[Br:10]

Participants

4

Reactant 3

HCID 1118Sulfuric AcidHCID 24434Potassium NitrateHCID 13268177Carbonic acid, 2-bromo-4-fluorophenyl methyl ester

Product 1

HCID 13268178Methyl 2-bromo-4-fluoro-5-nitrophenoxyformateYield 92%

Conditions

Temperature
0 °C

Procedure

(2-Bromo-4-fluoro-phenyl) methyl carbonate (8.25 g, 33.13 mmol) was added portionwise to conc. H2SO4 (45 mL) to generate a colorless homogeneous solution. This solution was then cooled to 0° C. and KNO3 (3.7 g, 36.44 mmol) was added portionwise maintaining the internal temperature below 5° C. The reaction was stirred for 2 h and then poured on ice-water and the aqueous layer was extracted with DCM (3×10 mL). The combined organic layer was dried over Na2SO4, filtered and concentrated. The residue was then purified by silica gel column chromatography using 15% EtOAc/hexane gradient to yield 2-bromo-4-fluoro-5-nitrophenyl methyl carbonate (8.93 g, 92%) 1H NMR (400 MHz, CDCl3) δ 8.05 (d, J=6.7 Hz, 1H), 7.65 (d, J=9.6 Hz, 1H), 4.01 (s, 3H).

Workup

  1. temperaturemaintaining the internal temperature below 5° C
  2. additionpoured on ice-water
  3. extractionthe aqueous layer was extracted with DCM (3×10 mL)
  4. dry with materialThe combined organic layer was dried over Na2SO4
  5. filtrationfiltered
  6. concentrationconcentrated
  7. customThe residue was then purified by silica gel column chromatography

Sources & evidence

ORD record
ord-dc8e48bbf1f54ffeac2a3c162f3ac15e
Source dataset
uspto-grants-2013_01
Patent number
US08354427B2

Reaction notes

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