Reaction #817386

Reaction equation

o-phenylenediamine

benzo[b]thiophene-2-sulfonyl chloride

→

benzo[b]thiophene-2-sulfonic acid (2-amino-phenyl)-amide

Yield 78.8%

Solvents

DCM

pyridine

DCM

Conditions

Workup

1. 1
   WashThe organic phase was washed with water (2×25 mL) and 25 mL of brine
2. 2
   DryingThe organic phase was dried over anhydrous sodium sulfate
3. 3
   Concentrationconcentrated under vacuum
4. 4
   OtherThe residue obtained
5. 5
   Otherwas purified by flash column chromatography
6. 6
   Washeluting with DCM/EtOAc

Procedure

To a solution of o-phenylenediamine (5 mmol) in DCM (25 mL) and pyridine (5 mL) at 0° C., benzo[b]thiophene-2-sulfonyl chloride (5.5 mmol) was added in small portions. The reaction mixture was then gradually warmed to RT with stirring continued until the reaction was complete as determined by TLC or LC-MS. The reaction mixture was then diluted with DCM (25 mL). The organic phase was washed with water (2×25 mL) and 25 mL of brine. The organic phase was dried over anhydrous sodium sulfate, and concentrated under vacuum. The residue obtained was purified by flash column chromatography eluting with DCM/EtOAc to give 1.2 g of benzo[b]thiophene-2-sulfonic acid (2-amino-phenyl)-amide. Tr 0.94 min, MS: 305.7 (M+1)+. 1H NMR (DMSO-d6, 400 MHz): δ 6.40 (t, 1H), 6.60 (d, 1H), 6.78 (d, 1H), 6.89 (t, 1H), 7.45 (t, 1H), 7.50 (t, 1H), 7.80 (s, 1H), 7.90 (d, 1H), 8.80 (d, 1H) ppm.

Source