Chloroform → 3-Methoxy-dihydrothiophene-4-carboxylic acid methyl ester

HRID 1733585Notes

Reaction equation

HRID 1733585 reaction equation
[N+](=C)=[N-].[CH3:4][O:5][C:6]([CH:8]1[CH2:12][S:11][CH2:10][C:9]1=[O:13])=[O:7].[CH:14](Cl)(Cl)Cl>CCOCC>[CH3:4][O:5][C:6]([C:8]1[CH:9]([O:13][CH3:14])[CH2:10][S:11][CH:12]=1)=[O:7]

Participants

5

Reactant 3

HCID 6212ChloroformHCID 9550DiazomethaneHCID 984243-Thiophenecarboxylic acid, tetrahydro-4-oxo-, methyl ester

Product 1

HCID 540483033-Methoxy-dihydrothiophene-4-carboxylic acid methyl esterYield 86%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Conditions

Temperature
0 °C

Procedure

15 parts by volume of an 0.5 molar solution of diazomethane in ether are added in the course of about 10 minutes to a solution, cooled to 0° C., of 1.6 parts of 3-oxo-tetrahydrothiophene-4-carboxylic acid methyl ester in 10 parts by volume of dry chloroform. The solution is stirred for 21 hours at 0° C., flushed with nitrogen to remove excess diazomethane and concentrated under reduced pressure. The residue is recrystallized from methylene chloride/petroleum ether. 1.5 parts (86% of theory) of 3-methoxy-dihydrothiophene-4-carboxylic acid methyl ester of melting point 79°-81° C. are obtained.

Workup

  1. customflushed with nitrogen
  2. customto remove excess diazomethane
  3. concentrationconcentrated under reduced pressure
  4. customThe residue is recrystallized from methylene chloride/petroleum ether

Sources & evidence

ORD record
ord-8bbcc9661a8e42a78a07fc469b45c883
Source dataset
uspto-grants-1980_12
Patent number
US04242518

Reaction notes

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