Hydrochloric Acid → Ethyl 5-hydroxybenzofuran-2-carboxylate

HRID 1058574

Reaction equation

HRID 1058574 reaction equation
[Cl-].[Al+3].[Cl-].[Cl-].C(S)C.C[O:9][C:10]1[CH:11]=[CH:12][C:13]2[O:17][C:16]([C:18]([O:20][CH2:21][CH3:22])=[O:19])=[CH:15][C:14]=2[CH:23]=1.Cl>ClCCl.O>[OH:9][C:10]1[CH:11]=[CH:12][C:13]2[O:17][C:16]([C:18]([O:20][CH2:21][CH3:22])=[O:19])=[CH:15][C:14]=2[CH:23]=1

Participants

7

Reactant 4

HCID 313Hydrochloric AcidHCID 6343EthanethiolHCID 5212832-Benzofurancarboxylic acid, 5-methoxy-, ethyl esterHCID 6451240Aluminum(III) Chloride

Product 1

HCID 22228632Ethyl 5-hydroxybenzofuran-2-carboxylateYield 77%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6344DichloromethaneSolvent

Procedure

To a mixture of aluminum chloride (6.3 g, 47.7 mmol) and ethanethiol (4.5 g, 72.9 mmol) in dichloromethane (81 mL) at 0° C. was added ethyl 5-methoxybenzofuran-2-carboxylate (3.0 g, 13.6 mmol). After stirring for 16 h at room temperature, the mixture was poured into water, acidified with 3N HCl and extracted with dichloromethane (2x). The organic layers were combined, washed with brine, collected, dried (MgSO4), filtered and concentrated. The residue was purified by column chromatography (silica gel, ethyl acetate/hexane) to yield the title compound as a white solid (2.16 g, 77%). 1H NMR (400 MHz, CDCl3) δ 7.45 (m, 2H), 7.08 (m, 1H), 7.02 (m, 1H), 5.35 (s b, 1H), 4.44 (q, 2H), 1.42 (t, 3H).

Workup

  1. extractionextracted with dichloromethane (2x)
  2. washwashed with brine
  3. customcollected
  4. dry with materialdried (MgSO4)
  5. filtrationfiltered
  6. concentrationconcentrated
  7. customThe residue was purified by column chromatography (silica gel, ethyl acetate/hexane)

Sources & evidence

ORD record
ord-5292b85848ff4c28acefb19b4c2edb28
Source dataset
uspto-grants-2003_02
Patent number
US06518267B1

Linked notes

Loading…