Acetic Anhydride → methyl 3-acetamidothiophene-2-carboxylate

HRID 1825913Notes

Reaction equation

HRID 1825913 reaction equation
[C:1](OC(=O)C)(=[O:3])[CH3:2].[NH2:8][C:9]1[CH:13]=[CH:12][S:11][C:10]=1[C:14]([O:16][CH3:17])=[O:15]>C1(C)C=CC=CC=1>[C:1]([NH:8][C:9]1[CH:13]=[CH:12][S:11][C:10]=1[C:14]([O:16][CH3:17])=[O:15])(=[O:3])[CH3:2]

Participants

4

Reactant 2

HCID 7918Acetic AnhydrideHCID 89652Methyl 3-amino-2-thiophenecarboxylate

Product 1

HCID 729216methyl 3-acetamidothiophene-2-carboxylate

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Conditions

Temperature
0 °C

Procedure

With simultaneous heating in an oil bath, 567 ml of acetic anhydride are added dropwise to a mixture of 942 g of methyl 3-aminothiophene-2-carboxylate and 1000 ml of toluene, and the mixture is then boiled under reflux conditions for 1½ hours and subsequently cooled in an ice bath to about 0° C. The crystals are filtered off and washed twice with a little isopropanol and twice with diisopropyl ether. Methyl 3-acetylaminothiophene-2-carboxylate can be obtained from the filtrate by further concentration and crystallization. M.p. 93-95° C.

Workup

  1. temperatureWith simultaneous heating in an oil bath
  2. waitthe mixture is then boiled under reflux conditions for 1½ hours
  3. filtrationThe crystals are filtered off
  4. washwashed twice with a little isopropanol and twice with diisopropyl ether

Sources & evidence

ORD record
ord-94a7a1035b254e73b47fbf6abfb45929
Source dataset
uspto-grants-2006_05
Patent number
US07049333B2

Reaction notes

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