Hydrochloric Acid → Methyl 5-amino-1-benzothiophene-2-carboxylate

HRID 736512Notes

Reaction equation

HRID 736512 reaction equation
[CH3:1][O:2][C:3]([C:5]1[S:9][C:8]2[CH:10]=[CH:11][C:12]([N+:14]([O-])=O)=[CH:13][C:7]=2[CH:6]=1)=[O:4].Cl>CO.[Fe]>[CH3:1][O:2][C:3]([C:5]1[S:9][C:8]2[CH:10]=[CH:11][C:12]([NH2:14])=[CH:13][C:7]=2[CH:6]=1)=[O:4]

Participants

5

Reactant 2

HCID 313Hydrochloric AcidHCID 1489057Methyl 5-nitro-1-benzothiophene-2-carboxylate

Product 1

HCID 2824064Methyl 5-amino-1-benzothiophene-2-carboxylate

Reagents, catalysts & solvents 2

HCID 23925IronCatalystHCID 887MethanolSolvent

Procedure

A suspension of 584 (3.52 g, 14.8 mmol) in methanol (100 ml) was treated with Fe powder (6.63 g, 118.7 mmol). The resulting suspension was heated to reflux, and 12M HCl (8.5 ml) was slowly added over 15 min. The resulting green dark suspension was refluxed for an additional 3 h, then cooled and concentrated. The residue was taken up in EtOAc and washed with saturated aqueous NaHCO3, then brine, dried over MgSO4, filtered and concentrated to afford (2.57 g, 84%). 1H NMR: (DMSO) δ (ppm): 7.92 (s, 1H), 7.65 (d, J=8.8 Hz, 1H), 7.05 (d, J=1.5 Hz, 1H), 6.88 (dd, J=1.8, 8.4 Hz, 1H), 5.27 (s, 2H), 3.85 (s, 3H). LRMS: 207.0 (Calc.); 208.1 (found).

Workup

  1. temperatureThe resulting suspension was heated
  2. temperatureto reflux
  3. temperatureThe resulting green dark suspension was refluxed for an additional 3 h
  4. temperaturecooled
  5. concentrationconcentrated
  6. washwashed with saturated aqueous NaHCO3
  7. dry with materialbrine, dried over MgSO4
  8. filtrationfiltered
  9. concentrationconcentrated
  10. customto afford (2.57 g, 84%)

Sources & evidence

ORD record
ord-fe56e52c22d84f04a523a134b5497340
Source dataset
uspto-grants-2009_09
Patent number
US07595343B2

Reaction notes

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