Reacción #1144433

Ecuación de reacción

acetic acid

lithium diisopropylamide

1-ethoxymethyl-2-thiouracil

tetrahydrofuran

tetrahydrofuran

tetrahydrofuran

diphenyl disulfide

tetrahydrofuran

→

1-ethoxymethyl-6-phenylthio-2-thiouracil

Rendimiento 73.0%

Disolventes

ethyl acetate

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONwas added dropwise over 15 minutes
2. 2
   Otroto react for 20 minutes
3. 3
   Otrobrought to room temperature
4. 4
   LavadoThe mixture was washed with water (3 ml×5) and saturated aqueous solution of sodium hydrogencarbonate (twice),
5. 5
   Otrodried on magnesium sulfate
6. 6
   Concentraciónconcentrated under reduced pressure
7. 7
   OtroThe residue was purified by silica gel chromatography (ethyl acetate/hexane=3:17)
8. 8
   Otrocrystallized from ethyl acetate

Procedimiento

Then, 3.3 ml lithium diisopropylamide solution in tetrahydrofuran (2.1M) was added to 9 ml of tetrahydrofuran under a nitrogen atmosphere at −70° C., to which a solution of 0.56 g (3.0 mmol) of 1-ethoxymethyl-2-thiouracil in 3 ml of tetrahydrofuran was added dropwise over 15 minutes. After stirring for 1 hour at −70° C., the reaction mixture was added with a solution of 0.85 g (3.9 mmol) of diphenyl disulfide in 1 ml of tetrahydrofuran dropwise over 10 minutes and allowed to react for 20 minutes. The reaction mixture was added with 1 ml of acetic acid, brought to room temperature and then added with 30 ml of ethyl acetate. The mixture was washed with water (3 ml×5) and saturated aqueous solution of sodium hydrogencarbonate (twice), dried on magnesium sulfate and concentrated under reduced pressure. The residue was purified by silica gel chromatography (ethyl acetate/hexane=3:17), crystallized from ethyl acetate to obtain 0.64 g of 1-ethoxymethyl-6-phenylthio-2-thiouracil (Yield: 73%).

Fuente