Hydrochloric Acid → Methyl 4-aminothiophene-3-carboxylate

HRID 902507Notes

Reaction equation

HRID 902507 reaction equation
Cl.[CH3:2][O:3][C:4]([CH:6]1[C:10](=[N:11]O)[CH2:9][S:8][CH2:7]1)=[O:5]>CCOCC.CO>[CH3:2][O:3][C:4]([C:6]1[C:10]([NH2:11])=[CH:9][S:8][CH:7]=1)=[O:5]

Participants

5

Reactant 2

HCID 313Hydrochloric AcidHCID 736752764-Hydroxyimino-tetrahydro-thiophene-3-carboxylic acid methyl ester

Product 1

HCID 2777610Methyl 4-aminothiophene-3-carboxylateYield 111.3%

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 3283Diethyl EtherSolvent

Procedure

HCl (1M solution in ether, 125 mL) was added slowly to a solution of 4-hydroxyimino-tetrahydro-thiophene-3-carboxylic acid methyl ester (34) (18.30 g, 104 mmol) in dry ether (200 mL) and dry methanol (50 mL) stirred at room temperature. The solution was further stirred at room temperature under argon for 24 h. The solids formed were filtered, washed by cold ether, and dried to yield 18.20 g (91%) of 4-amino-thiophene-3-carboxylic acid methyl ester as the hydrochloride salt. MP 198° C.; 1H NMR (400 MHz, DMSO-d6) δ 3.86 (s, 3H), 7.22 (d, J=2.4 Hz, 1H), 8.37 (d, J=3.2 Hz, 1H) ppm; MS m/z=158 amu (M++1).

Workup

  1. stirringThe solution was further stirred at room temperature under argon for 24 h
  2. customThe solids formed
  3. filtrationwere filtered
  4. washwashed by cold ether
  5. customdried

Sources & evidence

ORD record
ord-4ad55c327e434144a0263f7b790a8d8c
Source dataset
uspto-grants-2008_04
Patent number
US07365200B2

Reaction notes

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