2-Chloro-N-(2-hydroxyethyl)-5-nitro-benzenesulfonamide → 8-Amino-3,4-dihydro-2H-benzo[b][1,4,5]oxathiazepine 1,1-Dioxide

Participants

Reaction Conditions

Reaction Steps

244 g of 8-nitro-3,4-dihydro-(2H)-5,1,2-benzoxathiazine 1,1-dioxide, which is accessible by an intramolecular condensation reaction from 2-chloro-5-nitro-N-(2-hydroxyethyl)-benzenesulphonamide (DOS (German Published Specification) 1,670,759), are suspended in 600 ml of methanol and are reduced in the presence of 3 g of freshly prepared Raney nickel as catalyst by injecting three times the equimolar amount of hydrogen in an autoclave at 50° C. When the reduction is complete, the catalyst is removed from the hot reaction solution, from which the amino compound crystallizes out in fine flakes after cooling to 0° C. 205 g of 8-amino-3,4-dihydro-(2H)-5,1,2-benzoxathiazepine 1,1-dioxide of the formula ##STR17## melting point 179° C. are obtained after filtering off with suction and drying.

Provenance & Evidence