Hydrochloric Acid → 8-Oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid

HRID 426530Notes

Reaction equation

HRID 426530 reaction equation
C[Si]([CH:5]([Si](C)(C)C)[C:6]([NH2:8])=[O:7])(C)C.[CH2:13]1O[CH:14]1[CH3:15].C1(C)C=C[C:20]([S:23]Cl)=CC=1.[C:26](=[O:29])(O)[O-:27].[Na+].Cl>C(Cl)Cl>[O:7]=[C:6]1[N:8]2[CH:20]([S:23][CH2:13][CH:14]=[C:15]2[C:26]([OH:27])=[O:29])[CH2:5]1

Participants

7

Reactant 5

HCID 313Hydrochloric AcidHCID 6378Propylene OxideHCID 516892Sodium BicarbonateHCID 11019146HCID 11019146, compoundHCID 11708267Bistrimethylsilylacetamid

Product 1

HCID 190919938-Oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

A mixture of 4 g. (16.7 mmol.) of 7β-amino-3-[(acetyloxy)-methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid (i.e. 7-ACA), 8.3 ml. (33.4 mmol.) of bis(trimethylsilyl)-acetamide, pulverized molecular sieves (4A, ≃1000 beads), 16 ml. of propylene oxide, and 320 ml. of methylene chloride is stirred at 26° for 1.5 hours under a nitrogen atmosphere. The reaction mixture is cooled to 0° and 10.07 g. (66.8 mmol.) of p-toluenesulfenyl chloride is added dropwise over 20 minutes. The mixture is stirred at ambient temperature for three hours, and then poured into 5% sodium bicarbonate solution. The inorganic layer is acidified by the addition of 1 N HCl and extracted twice with 200 ml. of ethyl acetate. The combined organic extracts are dried over Na2SO4, and then concentrated under reduced pressure to a tan foam. The foam is triturated with ethyl ether to yield 1.75 g. of a tan crystalline material. Recrystallization without heating from methanol/acetone/ether/hexane affords pure pale yellow crystalline 7-[[(4-methylphenyl)thio]imino]-3-](acetyloxy)methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid; m.p. 204°-205.5°.

Workup

  1. additionA mixture of 4 g
  2. temperatureThe reaction mixture is cooled to 0°
  3. extractionextracted twice with 200 ml
  4. dry with materialThe combined organic extracts are dried over Na2SO4
  5. concentrationconcentrated under reduced pressure to a tan foam
  6. customThe foam is triturated with ethyl ether
  7. customto yield 1.75 g
  8. customRecrystallization
  9. temperaturewithout heating from methanol/acetone/ether/hexane

Sources & evidence

ORD record
ord-e6d3c5ed06c14078a631cfdb5db5a862
Source dataset
uspto-grants-1979_10
Patent number
US04169946

Reaction notes

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