Reaktion #54319

Reaktionsgleichung

hydrochloric acid

tetrahydrofuran

benzhydryl 7-phenoxyacetamido-3-formyl-3-cephem-4-carboxylate-1-oxide

(1-methyl-1H-tetrazol-5-yl)methylenetriphenylphosphorane

→

benzhydryl 7-phenoxyacetamido-3-(1-methyl-1H-tetrazol-5-yl)vinyl-3-cephem-4-carboxylate-1-oxide

Ausbeute 59.0%

Lösungsmittel

ethyl acetate

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturafter cooling to -5°--10° C.
2. 2
   WaschenThe organic layer was washed with five portions of a saturated aqueous sodium chloride solution
3. 3
   Trocknendried over anhydrous sodium sulfate
4. 4
   workup.DISTILLATIONThe solvent was distilled off under reduced pressure
5. 5
   Sonstigeto leave a solid residue
6. 6
   workup.STIRRINGstirred at room temperature for 20 minutes
7. 7
   Filtrationfiltered
8. 8
   Sonstigeleaving a precipitate

Vorschrift

To 130 ml of anhydrous tetrahydrofuran was added 5.35 g of benzhydryl 7-phenoxyacetamido-3-formyl-3-cephem-4-carboxylate-1-oxide, and, after cooling to -5°--10° C., further added 4.3 g of (1-methyl-1H-tetrazol-5-yl)methylenetriphenylphosphorane. The mixture was stirred at that temperature for 5 hours and poured into a mixture of ethyl acetate and ice-water. The resulting mixture was then made acidic with 10 ml of 5% hydrochloric acid. The organic layer was washed with five portions of a saturated aqueous sodium chloride solution and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to leave a solid residue. The residue was, after addition of approximately 30 ml of methanol, stirred at room temperature for 20 minutes and filtered leaving a precipitate. There was obtained 3.62 g of benzhydryl 7-phenoxyacetamido-3-(1-methyl-1H-tetrazol-5-yl)vinyl-3-cephem-4-carboxylate-1-oxide as a crystalline powder. The filtrate was evaporated under redueced pressure to dryness, and the obtained residue was developed through silica gel column with ethyl acetate to give 600 mg of the crystals additionally.

Quelle