Acetic Anhydride → Ethyl 2-formamidothiazol-4-acetate

HRID 1155153Notes

Reaction equation

HRID 1155153 reaction equation
[C:1](OC(=O)C)(=[O:3])C.[NH2:8][C:9]1[S:10][CH:11]=[C:12]([CH2:14][C:15]([O:17][CH2:18][CH3:19])=[O:16])[N:13]=1>C(O)=O>[CH:1]([NH:8][C:9]1[S:10][CH:11]=[C:12]([CH2:14][C:15]([O:17][CH2:18][CH3:19])=[O:16])[N:13]=1)=[O:3]

Participants

5

Reactant 3

HCID 7918Acetic AnhydrideHCID 1044544-Thiazoleacetic acid, 2-amino-, ethyl esterHCID 178470764HCID 178470764, compound

Product 1

HCID 688091Ethyl 2-formamidothiazol-4-acetate

Reagents, catalysts & solvents 1

HCID 284Formic AcidSolvent

Procedure

To acetic anhydride (384 ml.) was added dropwise formic acid (169.2 ml.) over 15 to 20 minutes under cooling below 35° C., and the mixture was stirred for 1 hour at 55° to 60° C. To the mixture was added ethyl 2-(2-aminothiazol-4-yl)acetate, which can be represented as ethyl 2-(2-imino-2,3-dihydrothiazol-4-yl)acetate, (506 g.) over 15 to 20 minutes under ice-cooling and stirring, and then the mixture was stirred for 1 hour at room temperature. After the reaction, the solvents were distilled off. To the residue was added diisopropyl ether (2500 ml.), and the mixture was stirred for 1 hour at room temperature. The precipitates were collected by filtration, washed with diisopropyl ether and then dried to give ethyl 2-(2-formylaminothiazol-4-yl)acetate, which can be represented as ethyl 2-(2-formylimino-2,3-dihydrothiazol-4-yl)acetate, (451.6 g.), mp 125° to 126° C. The remaining filtrate was concentrated, and the residue was washed with diisopropyl ether (500 ml.) and then dried to give further the same object compound (78.5 g.).

Workup

  1. temperatureunder cooling below 35° C.
  2. temperaturecooling
  3. stirringstirring
  4. stirringthe mixture was stirred for 1 hour at room temperature
  5. customAfter the reaction
  6. distillationthe solvents were distilled off
  7. additionTo the residue was added diisopropyl ether (2500 ml.)
  8. stirringthe mixture was stirred for 1 hour at room temperature
  9. filtrationThe precipitates were collected by filtration
  10. washwashed with diisopropyl ether
  11. customdried

Sources & evidence

ORD record
ord-58cc2e870ee546b5bf39ba883709aeb0
Source dataset
uspto-grants-1981_11
Patent number
US04299829

Reaction notes

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