Water → Methyl 5-bromo-3-hydroxythiophene-2-carboxylate

HRID 1947548Notes

Reaction equation

HRID 1947548 reaction equation
B(Br)(Br)Br.[CH3:5][O:6][C:7]([C:9]1[S:10][C:11]([Br:16])=[CH:12][C:13]=1[O:14]C)=[O:8].O>C(Cl)Cl>[CH3:5][O:6][C:7]([C:9]1[S:10][C:11]([Br:16])=[CH:12][C:13]=1[OH:14])=[O:8]

Participants

5

Reactant 3

HCID 962WaterHCID 25134Boron tribromideHCID 59857165Methyl 5-bromo-3-methoxythiophene-2-carboxylate

Product 1

HCID 59857018Methyl 5-bromo-3-hydroxythiophene-2-carboxylateYield 81.7%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

BBr3 (26 mL, 1.0 M in heptane, 25.9 mmol, 3.0 Eq.) was added dropwise to a stirred solution of 5-Bromo-3-methoxy-thiophene-2-carboxylic acid methyl ester (2.17 g, 8.62 mmol, 1.0 Eq.) in anhydrous DCM (100 mL) at −10° C. under nitrogen. After 1.5 hours, water (40 mL) was added and the aqueous layer extracted with DCM (3×20 mL). The combined organic extracts were dried (MgSO4) and concentrated in vacuo. The crude product was purified by column chromatography (50% Petroleum ether/DCM) to give the sub-title compound as a white solid (1.67 g, 7.04 mmol, 81%); 1H NMR (400 MHz, CDCl3) δ 3.90 (3H, s), 6.80 (1H, s), 9.68 (1H, br s).

Workup

  1. extractionthe aqueous layer extracted with DCM (3×20 mL)
  2. dry with materialThe combined organic extracts were dried (MgSO4)
  3. concentrationconcentrated in vacuo
  4. customThe crude product was purified by column chromatography (50% Petroleum ether/DCM)

Sources & evidence

ORD record
ord-b5dba19d0c954d56bc6e1c3622c5319f
Source dataset
uspto-grants-2013_03
Patent number
US08399478B2

Reaction notes

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