Reacción #8210

Ecuación de reacción

benzenesulfonyl chloride

ICl

CH2Cl2

5,7-difluoroindole

→

N-Benzenesulfonyl-3-iodo-5,7-difluoroindole

Rendimiento 87.0%

Disolventes

toluene

NaOH

toluene

pyridine

Condiciones de reacción

Tratamiento posterior

1. 1
   Lavadowashed with brine, 1N HCl, 1N NaOH
2. 2
   Secadodried (Na2SO4)
3. 3
   Filtraciónfiltered
4. 4
   Concentraciónconcentrated
5. 5
   workup.STIRRINGThe crude 3-iodo-5,7-difluoroindole is stirred in toluene (85 ml)
6. 6
   workup.STIRRINGthe resulting mixture is stirred 24 hours
7. 7
   OtroThe two phase reaction mixture
8. 8
   Lavadowashed with brine, dried(Na2SO4)
9. 9
   Filtraciónfiltered
10. 10
    Concentraciónconcentrated
11. 11
    Otrothe residue is triturated with diethyl ether/petroleum ether
12. 12
    FiltraciónThe resulting solid is filtered

Procedimiento

The 1.0 M ICl in CH2Cl2 (43 ml, 43 mmol) is added to a solution of 5,7-difluoroindole (6 g, 39 mmol) in 35 ml pyridine under N2 at 0° C. and the resulting mixture is stirred for 30 minutes. The reaction is diluted with toluene and washed with brine, 1N HCl, 1N NaOH, dried (Na2SO4), filtered and concentrated. The crude 3-iodo-5,7-difluoroindole is stirred in toluene (85 ml) and 5 N NaOH (70 ml), tetrabutylammonium bromide (1.25 g, 3.9 mmol), then benzenesulfonyl chloride (6.2 ml, 48 mmol) are added and the resulting mixture is stirred 24 hours. The two phase reaction mixture is diluted with toluene, washed with brine, dried(Na2SO4), filtered, concentrated and the residue is triturated with diethyl ether/petroleum ether. The resulting solid is filtered to give 14.2 g of N-Benzenesulfonyl-3-iodo-5,7-difluoroindole (87%).

Fuente