Reacción #213937

Ecuación de reacción

phosphorus oxychloride

2-[2-(2-thienyl)acetoxyimino]-2-(3-hydroxyphenyl)acetic acid

7-amino-3-(1-methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid

bis(trimethylsilyl)acetamide

→

7-[2-(2-(2-thienyl)acetoxyimino)-2-(3-hydroxyphenyl)acetamido]-3-(1methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid

Rendimiento 71.5%

Disolventes

ethyl acetate

Water

ethyl acetate

methylene chloride

Dimethylformamide

ethyl acetate

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONwas added the above obtained solution
2. 2
   workup.STIRRINGThen the reaction mixture was stirred for 1 hour at the same temperature
3. 3
   workup.STIRRINGthe mixture was stirred for 10 minutes
4. 4
   OtroThe ethyl acetate layer was separated
5. 5
   ExtracciónThe aqueous layer was extracted with ethyl acetate
6. 6
   LavadoThe extract was washed with a saturated aqueous solution of sodium chloride
7. 7
   Otrodried
8. 8
   workup.DISTILLATIONThe solvent was distilled off
9. 9
   Filtracióncollected by filtration
10. 10
    Lavadowashed

Procedimiento

Dimethylformamide (0.4 g.), phosphorus oxychloride (0.81 g.), methylene chloride (20 ml.), ethyl acetate (10 ml.) and 2-[2-(2-thienyl)acetoxyimino]-2-(3-hydroxyphenyl)acetic acid (syn isomer) (1.68 g.) were treated in a manner as in example 1(B) to give an ethyl acetate solution. On the other hand, 7-amino-3-(1-methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid (1.64 g.) and bis(trimethylsilyl)acetamide (3.55 g.) were dissolved in ethyl acetate (20 ml.) and stirred at -20° C., to which was added the above obtained solution. Then the reaction mixture was stirred for 1 hour at the same temperature. Water was added thereto and the mixture was stirred for 10 minutes. The ethyl acetate layer was separated. The aqueous layer was extracted with ethyl acetate. Two ethyl acetate layers were combined. The extract was washed with a saturated aqueous solution of sodium chloride and dried. The solvent was distilled off. The residue was pulverized with a mixed solution of diisopropylether and ether, collected by filtration and washed to give 7-[2-(2-(2-thienyl)acetoxyimino)-2-(3-hydroxyphenyl)acetamido]-3-(1methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid (syn isomer) (2.2 g.).

Fuente