Reacción #445549

Ecuación de reacción

isobutyl chloroformate

triethylamine

4(RS)-tetrahydropyranyloxy-2-(5-carboxypentylthio)-2-cyclopentenone

benzyl alcohol

→

4(RS)-tetrahydropyranyloxy-2-(5-benzyloxycarbonylpentyl-thio)-2-cyclopentenone

Rendimiento 51.0%

Disolventes

dichloromethane

dichloromethane

dichloromethane

dichloromethane

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.WAITthe reaction was carried out for 18 hours
2. 2
   Temperaturawhile gradually raising the temperature to room temperature
3. 3
   OtroAfter the reaction
4. 4
   Extracciónthe reaction mixture was extracted with ethyl acetate
5. 5
   LavadoThe extract was washed with an aqueous solution of hydrogen chloride
6. 6
   Secadoan aqueous solution of sodium bicarbonate, then dried
7. 7
   Concentraciónconcentrated
8. 8
   OtroThe resulting crude product was chromatographed on a silica gel column

Procedimiento

2.09 g (6.1 mmoles) of 4(RS)-tetrahydropyranyloxy-2-(5-carboxypentylthio)-2-cyclopentenone was dissolved in 20 ml of dichloromethane, and to this solution were added 5 ml of a dichloromethane solution of 956 mg (7 mmoles) of isobutyl chloroformate and 5 ml of a dichloromethane solution of 808 mg (8 mmoles) of triethylamine. The mixture was stirred at -78° C. for 30 minutes. Then, 5 ml of a dichloromethane solution of 864 mg (8 mmoles) of benzyl alcohol was added, and the reaction was carried out for 18 hours while gradually raising the temperature to room temperature. After the reaction, the reaction mixture was extracted with ethyl acetate. The extract was washed with an aqueous solution of hydrogen chloride and an aqueous solution of sodium bicarbonate, then dried, and concentrated. The resulting crude product was chromatographed on a silica gel column using hexane/ethyl acetate (3.5/1) as an eluent to give 1.30 g (3.11 mmoles; yield 51%) of 4(RS)-tetrahydropyranyloxy-2-(5-benzyloxycarbonylpentyl-thio)-2-cyclopentenone.

Fuente