Reacción #833558

Ecuación de reacción

hydrogen

phenylisocyanate

sodium hydride

3,4-dihydro-2,6-dimethyl-3-oxo-2H-thieno[2,3-e]-1,2-thiazine 1,1-dioxide

→

3,4-dihydro-2,6-dimethyl-3-oxo-2H-thieno[2,3-e]-1,2-thiazine-4-carboxanilide 1,1-dioxide

Rendimiento 69.0%

Disolventes

tetrahydrofurane

tetrahydrofurane

tetrahydrofurane

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONwere added at −5° C
2. 2
   Otrowas quenched with ice/water and by addition of dilute HCl
3. 3
   Extracciónextracted with CH2Cl2 (2 times)
4. 4
   LavadoThe combined CH2Cl2 extracts were washed
5. 5
   Otrodried
6. 6
   Concentraciónconcentrated
7. 7
   Otroto give 6 g crude product
8. 8
   OtroThis material was recrystallized from ethanol

Procedimiento

To a suspension of 0.78 g (32.5 mmol) sodium hydride in 50 mL tetrahydrofurane was added at −5° C. under N2 a solution of 5 g (21.6 mmol) 3,4-dihydro-2,6-dimethyl-3-oxo-2H-thieno[2,3-e]-1,2-thiazine 1,1-dioxide in 50 mL tetrahydrofurane. After termination of the hydrogen formation 6.5 g (55 mmol) phenylisocyanate dissolved in 50 mL tetrahydrofurane were added at −5° C. After stirring at room temperature the resulting mixture was quenched with ice/water and by addition of dilute HCl and then extracted with CH2Cl2 (2 times). The combined CH2Cl2 extracts were washed, dried and concentrated to give 6 g crude product. This material was recrystallized from ethanol to give 5.2 g 3,4-dihydro-2,6-dimethyl-3-oxo-2H-thieno[2,3-e]-1,2-thiazine-4-carboxanilide 1,1-dioxide.

Fuente