3-Thiophenecarboxylic acid, tetrahydro-4-oxo-, methyl ester → Methyl 4-aminothiophene-3-carboxylate Hydrochloride

HRID 231646

Reaction equation

HRID 231646 reaction equation
O=[C:2]1[CH:6]([C:7]([O:9][CH3:10])=[O:8])[CH2:5][S:4][CH2:3]1.[ClH:11].[NH2:12]O>CO>[ClH:11].[NH2:12][C:2]1[C:6]([C:7]([O:9][CH3:10])=[O:8])=[CH:5][S:4][CH:3]=1

Participants

4

Reactant 2

HCID 984243-Thiophenecarboxylic acid, tetrahydro-4-oxo-, methyl esterHCID 443297Hydroxyamine hydrochloride

Product 1

HCID 2777609Methyl 4-aminothiophene-3-carboxylate HydrochlorideYield 57.6%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

3-Oxo-4-methoxycarbonyltetrahydrothiophene (28 g) was heated under reflux for 1 hour with hydroxylamine hydrochloride (11.5 g) in methanol (80 ml). The mixture was then cooled and a first crop was filtered off and washed with dry diethyl ether to afford the title compound (18.4 g, 57.6%) m.p. 203° to 205° C. On further cooling a second crop (2.7 g, 8.5%) was obtained, m.p. 201° to 202° C. The total yield was thus 66.1%.

Workup

  1. temperatureThe mixture was then cooled
  2. filtrationa first crop was filtered off
  3. washwashed with dry diethyl ether

Sources & evidence

ORD record
ord-bfaff0b14b7248de9e161e3a59afa063
Source dataset
uspto-grants-1989_07
Patent number
US04847386

Linked notes

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