4-cyclopropyl-7-nitro-4H-1,2,4-benzothiadiazine 1,1-dioxide → 7-amino-4-cyclopropyl-4H-1,2,4-benzothiadiazine 1,1-dioxide

Participants

Reaction Steps

To a solution of 4-cyclopropyl-7-nitro-4H-1,2,4-benzothiadiazine 1,1-dioxide (5 g; prepared in Step C of Example 41) in ethanol (180 mL) there is added 10 % palladium-on-carbon (500 mg). The suspension is placed in a hydrogenator under 10 atmospheres of H2 for 30 minutes at ambient temperature. The suspension is concentrated to dryness under reduced pressure and the residue is taken up in boiling acetone (300 mL). The insoluble material is removed by filtration in the hot state and is washed with boiling acetone. The filtrate is concentrated to dryness and the residue is recrystallised from methanol.

Provenance & Evidence