Reacción #65553

Ecuación de reacción

(2S, 4R)-4-methanesulfonyloxy-1-(4-nitrobenzyloxycarbonyl) -2-thiocarbamoylpyrrolidine

ethyl bromopyruvate

→

(2S,4R)-2- (4-carboxythiazol-2-yl)-4-methanesulfonyloxy-1-(4-nitrobenzyloxycarbonyl) pyrrolidine

Disolventes

dichloromethane

ethanol

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrothe mixture was evaporated
2. 2
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate
3. 3
   Lavadowashed with saturated sodium bicarbonate and brine successively
4. 4
   OtroThe dried organic layer was evaporated
5. 5
   workup.DISSOLUTIONthe residue was dissolved in tetrahydrofuran (15 ml) and in sodium hydroxide (15 ml)
6. 6
   workup.STIRRINGAfter stirring at 35°-45° C. for 1 hour
7. 7
   Otrothe mixture was evaporated
8. 8
   workup.ADDITIONpoured into ethyl acetate
9. 9
   workup.ADDITIONTo this mixture was added 1N hydrochloric acid (20 ml)
10. 10
    Otroorganic layer was separated
11. 11
    Lavadowashed with brine
12. 12
    OtroThe dried organic layer was evaporated

Procedimiento

To a solution of (2S, 4R)-4-methanesulfonyloxy-1-(4-nitrobenzyloxycarbonyl) -2-thiocarbamoylpyrrolidine (2.0 g) in dichloromethane (40 ml) was added a solution of ethyl bromopyruvate (1.04 ml) in absolute ethanol (10 ml) at 0° C. After stirring at room temperature for 2 hours, the mixture was evaporated. The residue was dissolved in ethyl acetate, and washed with saturated sodium bicarbonate and brine successively. The dried organic layer was evaporated and the residue was dissolved in tetrahydrofuran (15 ml) and in sodium hydroxide (15 ml). After stirring at 35°-45° C. for 1 hour, the mixture was evaporated and poured into ethyl acetate. To this mixture was added 1N hydrochloric acid (20 ml), and then organic layer was separated, and washed with brine. The dried organic layer was evaporated to give (2S,4R)-2- (4-carboxythiazol-2-yl)-4-methanesulfonyloxy-1-(4-nitrobenzyloxycarbonyl) pyrrolidine (1.54 g).

Fuente