Reacción #56558

Ecuación de reacción

2,2,2-trichloroethyl 2-methyl-7-(2-hydroxyimino-3-oxo-4-bromobutyramido)-3-cephem-4-carboxylate

diazomethane

→

2,2,2-trichloroethyl 2-methyl-7-(2-methoxyimino-3-oxo-4-bromobutyramido)-3-cephem-4-carboxylate

Disolventes

ethanol

diethyl ether

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturaice-cooling
2. 2
   Otrothe reaction
3. 3
   ConcentraciónAfter the reaction mixture was concentrated under reduced pressure
4. 4
   Filtracióncollected by filtration
5. 5
   Otrodried

Procedimiento

To a solution of 2,2,2-trichloroethyl 2-methyl-7-(2-hydroxyimino-3-oxo-4-bromobutyramido)-3-cephem-4-carboxylate (a mixture of syn and anti isomers) (1.2 g.) in ethanol (20 ml.) was added dropwise a solution of diazomethane (0.1 mole) in diethyl ether under stirring and ice-cooling to complete the reaction. After the reaction mixture was concentrated under reduced pressure, the residue was pulverized in diisopropyl ether, collected by filtration and then dried to give brown powder of 2,2,2-trichloroethyl 2-methyl-7-(2-methoxyimino-3-oxo-4-bromobutyramido)-3-cephem-4-carboxylate (a mixture of syn and anti isomers) (1.1 g.), mp 80° to 83° C. (dec.).

Fuente