Phosphorus oxychloride → 4-Amino-3-nitrobenzene-1-sulfonyl chloride

Participants

Reaction Steps

A mixure of o-nitroaniline-p-sulfonic acid sodium salt (25.00 g, 104 mmol) and phosphoryl chloride (75 mL, 804 mmol) under Argon was heated to reflux and vigorously stirred for 4 hours. After cooling to ambient temperature, the reaction mixture was carefully added to a large excess of ice. The resulting slurry was stirred for 15 min., filtered and dried under vacuum to provide o-nitroaniline-p-sulfonyl chloride (21.43 g, 87%) as a yellow solid. H1-NMR (dimethylsulfoxide-D6): 5.8 (b, 2H), 6.97 (d, 1H, J=8.8), 7.57 (m, 1H), 8.18 (d, 1H, J=2.0).

Provenance & Evidence