Reacción #709941

Ecuación de reacción

phosphorus pentachloride

7-(2-thienylacetamido)-3-(3-chloro-1-pyridiniomethyl)-3-cephem-4-carboxylate

N,N-dimethylaniline

1,3-butanediol

trimethylsilylchloride

→

7-amino-3-(3-chloro-1-pyridiniomethyl)-3-cephem-4-carboxylate dihydrochloride

Rendimiento 177.6%

Disolventes

methylene chloride

methylene chloride

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.STIRRINGunder stirring
2. 2
   workup.WAITwhich was continued for one hour at -30° to -25° C
3. 3
   Temperaturaunder cooling in an ice-bath
4. 4
   workup.STIRRINGstirring
5. 5
   workup.WAITwhich was continued for one hour at ambient temperature
6. 6
   FiltraciónThe resulting precipitate was filtered
7. 7
   Lavadowashed with methylene chloride
8. 8
   workup.DISSOLUTIONredissolved in methanol (50 ml)
9. 9
   workup.ADDITIONAfter the solution was treated with activated charcoal (1 g)
10. 10
    workup.ADDITIONthe filtrate was poured into acetone (500 ml)
11. 11
    workup.STIRRINGunder stirring
12. 12
    workup.WAITwhich was continued for 30 minutes at ambient temperature
13. 13
    FiltraciónThe resulting precipitate was filtered
14. 14
    Lavadowashed with acetone
15. 15
    Otrodried

Procedimiento

To a mixture of 7-(2-thienylacetamido)-3-(3-chloro-1-pyridiniomethyl)-3-cephem-4-carboxylate (22.5 g) and N,N-dimethylaniline (60.0 g) in methylene chloride (400 ml) was added dropwise trimethylsilylchloride (50.0 g) at ambient temperature under stirring, which was continued for 15 minutes at the same temperature. The reaction mixture was cooled to -30° C. and phosphorus pentachloride (31.2 g) was added thereto under stirring, which was continued for one hour at -30° to -25° C. The reaction mixture was added to a cold solution of 1,3-butanediol (45 g) in methylene chloride (400 ml) under cooling in an ice-bath and stirring, which was continued for one hour at ambient temperature. The resulting precipitate was filtered, washed with methylene chloride and redissolved in methanol (50 ml). After the solution was treated with activated charcoal (1 g), the filtrate was poured into acetone (500 ml) under stirring, which was continued for 30 minutes at ambient temperature. The resulting precipitate was filtered, washed with acetone and dried to give 7-amino-3-(3-chloro-1-pyridiniomethyl)-3-cephem-4-carboxylate dihydrochloride (17.7 g), mp. 160° to 165° C. (dec.).

Fuente