Acetic Acid → Methyl 3-hydroxy-5-methylthiophene-2-carboxylate

HRID 1200101Notes

Reaction equation

HRID 1200101 reaction equation
Cl[C:2]1([C:8]([O:10][CH3:11])=[O:9])[C:6](=[O:7])[CH:5]=[CH:4][S:3]1.S(=O)(=O)(O)O.[C:17](O)(=O)C>>[OH:7][C:6]1[CH:5]=[C:4]([CH3:17])[S:3][C:2]=1[C:8]([O:10][CH3:11])=[O:9]

Participants

4

Reactant 3

HCID 176Acetic Acid2×HCID 1118Sulfuric AcidHCID 15588102Methyl 2-chloro-3-oxo-2,3-dihydrothiophene-2-carboxylate

Product 1

HCID 587860Methyl 3-hydroxy-5-methylthiophene-2-carboxylate

Procedure

To a stirred suspension of 2-chloro-2-methoxycarbonylthiophen-3(2H)-one (6.35 g, 33 mmol) in acetic acid (20 ml) was added sulphuric acid (1.8 ml) in acetic acid (20 ml). The mixture was stirred until dissolved then methyl mercaptan was bubbled through for 0.5 hours (total approximately 2 g). The mixture was stirred at room temperature for 18 hours, poured onto ice-water and the oily precipitate extracted into dichloromethane. After evaporation of solvent the crude oil was used in the following preparation.

Workup

  1. dissolutionuntil dissolved
  2. custommethyl mercaptan was bubbled through for 0.5 hours (total approximately 2 g)
  3. stirringThe mixture was stirred at room temperature for 18 hours
  4. additionpoured onto ice-water
  5. extractionthe oily precipitate extracted into dichloromethane
  6. customAfter evaporation of solvent the crude oil
  7. customwas used in the following preparation

Sources & evidence

ORD record
ord-ed742053a5e74d63a9e3b810cbb989bd
Source dataset
uspto-grants-1990_02
Patent number
US04904686

Reaction notes

Loading…