Dichloroacetyl chloride → 7-Dichloroacetamido-3-(1,3,4-thiadiazol-2-ylthiomethyl)-3-cephem-4-carboxylic acid

HRID 328062Notes

Reaction equation

HRID 328062 reaction equation
[NH2:1][CH:2]1[C:19](=[O:20])[N:4]2[C:5]([C:16]([OH:18])=[O:17])=[C:6]([CH2:9][S:10][C:11]3[S:12][CH:13]=[N:14][N:15]=3)[CH2:7][S:8][C@H:3]12.C[Si](C([Si](C)(C)C)C(N)=O)(C)C.[Cl:33][CH:34]([Cl:38])[C:35](Cl)=[O:36]>C(Cl)Cl>[Cl:33][CH:34]([Cl:38])[C:35]([NH:1][CH:2]1[C:19](=[O:20])[N:4]2[C:5]([C:16]([OH:18])=[O:17])=[C:6]([CH2:9][S:10][C:11]3[S:12][CH:13]=[N:14][N:15]=3)[CH2:7][S:8][C@H:3]12)=[O:36]

Participants

5

Reactant 3

HCID 6593Dichloroacetyl chlorideHCID 11708267BistrimethylsilylacetamidHCID 128891877-Amino-3-(1,3,4-thiadiazol-2-ylthiomethyl)-3cephem-4-carboxylic acid

Product 1

HCID 706321437-Dichloroacetamido-3-(1,3,4-thiadiazol-2-ylthiomethyl)-3-cephem-4-carboxylic acidYield 80.6%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

7-Amino-3-(1,3,4-thiadiazol-2-ylthiomethyl)-3-cephem-4-carboxylic acid (6.61 g) was suspended in methylene chloride (60 ml) and bis(trimethylsilyl)acetamide was added to the suspension to give a solution. A solution of dichloroacetyl chloride (3.24 g) in methylene chloride (10 ml) was added to the solution obtained above at -20° C under stirring. The mixture was stirred at the same temperature for 20 minutes. Methylene chloride was distilled off under reduced pressure after addition of a little water. Water was added to the residue and the mixture was extracted with ethyl acetate. The extract was washed with saturated aqueous sodium chloride and dried, and the solvent was distilled off under reduced pressure. The residue was pulverized by treating with ether and precipitates were collected by filtration to give 7-dichloroacetamido-3-(1,3,4-thiadiazol-2-ylthiomethyl)-3-cephem-4-carboxylic acid (7.12 g).

Workup

  1. customto give a solution
  2. customobtained above at -20° C
  3. stirringThe mixture was stirred at the same temperature for 20 minutes
  4. distillationMethylene chloride was distilled off under reduced pressure
  5. additionafter addition of a little water
  6. additionWater was added to the residue
  7. extractionthe mixture was extracted with ethyl acetate
  8. washThe extract was washed with saturated aqueous sodium chloride
  9. customdried
  10. distillationthe solvent was distilled off under reduced pressure
  11. additionby treating with ether
  12. customprecipitates
  13. filtrationwere collected by filtration

Sources & evidence

ORD record
ord-1f7b5ce0e0bc4e2cbba634fe398c6d0e
Source dataset
uspto-grants-1977_04
Patent number
US04016160

Reaction notes

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