Réaction #93028

Équation de réaction

methylcellosolve

Pyridine

phosphorus pentachloride

Benzhydryl 7-phenylacetamido-3-(2,2-dibromovinyl)-3-cephem-4-carboxylate

→

benzhydryl 7-amino-3-(2,2-dibromovinyl)-3-cephem-4-carboxylate

Rendement 82.6%

Solvants

methylene chloride

water

Conditions de réaction

Traitement

1. 1
   workup.STIRRINGstirred for two-hours
2. 2
   workup.STIRRINGthe resulting solution was stirred for an hour
3. 3
   Lavagethe separated organic layer was washed in turn with a saturated aqueous solution of sodium bicarbonate and brine
4. 4
   Autredried
5. 5
   AutreThe solvent was evaporated

Mode opératoire

Pyridine (0.39 ml) was added to a suspension of phosphorus pentachloride (1.01 ml) in dry methylene chloride (25 ml) at 5° C., and the mixture was stirred at ambient temperature for 30 minutes. Benzhydryl 7-phenylacetamido-3-(2,2-dibromovinyl)-3-cephem-4-carboxylate (2.5 g) was added to the above mixture at -10° C. and stirred for two-hours. Then, methylcellosolve (2.3 ml) was added to the reaction mixture at -30° C. and the resulting solution was stirred for an hour. To the above solution was added 5 ml of water and the separated organic layer was washed in turn with a saturated aqueous solution of sodium bicarbonate and brine, dried. The solvent was evaporated to give benzhydryl 7-amino-3-(2,2-dibromovinyl)-3-cephem-4-carboxylate (1.7 g).

Source