1-(4-aminophenyl)-N,N-dimethylmethanesulfonamide

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of 4.30 g (20.1 mmol, 1.0 equiv.) of 4-amino-N,N-dimethylbenzenemethanesulfonamide in 40 mL of concentrated aqueous hydrochloric acid and 20 mL of water cooled to 0° C. was added a solution of 1.38 g (20.1 mmol, 1.0 equiv.) of sodium nitrite in 20 mL of water dropwise. The reaction mixture became homogeneous during the addition. The reaction was stirred for fifteen minutes at 0° C. after the addition was complete. Meanwhile a solution of 22.6 g (100 mmol, 5.0 equiv.) of stannous chloride dihydrate in 40 mL of concentrated aqueous hydrochloric acid was prepared and cooled to -40° C. The solution of the diazonium salt was filtered into the stannous chloride solution. The reaction was allowed to warm to room temperature over the course of one hour. The reaction was then recooled to 0° C. and the precipitated product was collected by filtration. The solid was dried at 65° C. at 0.05 mm Hg for 45 minutes to yield 5.02 g (94%) of 4 -hydrazinyl-N,N-dimethylbenzenemethanesulfonamide hydrochloride. The reaction mixture became homogeneous during the addition after the addition cooled to -40° C The solution of the diazonium salt was filtered into the stannous chloride solution to warm to room temperature over the course of one hour was then recooled to 0° C. the precipitated product was collected by filtration The solid was dried at 65° C. at 0.05 mm Hg for 45 minutes

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 22.3 g of crude 4-nitro-N,N-dimethyl-benzenemethanesulfonamide (contaminated with dimethylamine hydrochloride as described above) in 45 mL of 2N hydrochloric acid, 100 mL of ethanol and 200 mL of water was added 5.0 g of 10% palladium on carbon. The mixture was hydrogenated in a Parr apparatus at 60 to 50 psi for three hours. The mixture was filtered and the ethanol removed in vacuo. The resulting aqueous solution was treated with 15% aqueous potassium hydroxide. Precipitate began forming at pH four. Addition of potassium hydroxide was continued until the pH had reached nine. The product was isolated by filtration and dried for sixteen hours at 65° C. at 0.05 mm Hg to give 21.0 g (83%, two steps) of 4-amino-N,N-dimethylbenzenemethanesulfonamide. The mixture was filtered the ethanol removed in vacuo The resulting aqueous solution was treated with 15% aqueous potassium hydroxide Precipitate began forming at pH four The product was isolated by filtration dried for sixteen hours at 65° C. at 0.05 mm Hg

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a suspension of 4.30 g (20.1 mmol, 1.0 equiv.) of 4-amino-N,N-dimethylbenzenemethanesulfonamide in 40 mL of concentrated aqueous hydrochloric acid and 20 mL of water cooled to 0° C. was added a solution of 1.38 g (20.1 mmol, 1.0 equiv.) of sodium nitrite in 20 mL of water dropwise. The reaction mixture became homogeneous during the addition. The reaction was stirred for fifteen minutes at 0° C. after the addition was complete. Meanwhile a solution of 22.6 g (100 mmol, 5.0 equiv.) of stannous chloride dihydrate in 40 mL of concentrated aqueous hydrochloric acid was prepared and cooled to -40° C. The solution of the diazonium salt was filtered into the stannous chloride solution. The reaction was allowed to warm to room temperature over the course of one hour. The reaction was then recooled to 0° C. and the precipitated product was collected by filtration. The solid was dried at 65° C. at 0.05 mm Hg for 45 minutes to yield 5.02 g (94%) of 4 -hydrazinyl-N,N-dimethylbenzenemethanesulfonamide hydrochloride. The reaction mixture became homogeneous during the addition after the addition cooled to -40° C The solution of the diazonium salt was filtered into the stannous chloride solution to warm to room temperature over the course of one hour was then recooled to 0° C. the precipitated product was collected by filtration The solid was dried at 65° C. at 0.05 mm Hg for 45 minutes

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 22.3 g of crude 4-nitro-N,N-dimethyl-benzenemethanesulfonamide (contaminated with dimethylamine hydrochloride as described above) in 45 mL of 2N hydrochloric acid, 100 mL of ethanol and 200 mL of water was added 5.0 g of 10% palladium on carbon. The mixture was hydrogenated in a Parr apparatus at 60 to 50 psi for three hours. The mixture was filtered and the ethanol removed in vacuo. The resulting aqueous solution was treated with 15% aqueous potassium hydroxide. Precipitate began forming at pH four. Addition of potassium hydroxide was continued until the pH had reached nine. The product was isolated by filtration and dried for sixteen hours at 65° C. at 0.05 mm Hg to give 21.0 g (83%, two steps) of 4-amino-N,N-dimethylbenzenemethanesulfonamide. The mixture was filtered the ethanol removed in vacuo The resulting aqueous solution was treated with 15% aqueous potassium hydroxide Precipitate began forming at pH four The product was isolated by filtration dried for sixteen hours at 65° C. at 0.05 mm Hg

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A suspension of N,N-dimethyl-4-nitrobenzenemethanesulphonamide (4.2 g) in methanol (300 ml) was hydrogenated over pre-reduced 10% palladium oxide on charcoal (1 g) at atmospheric pressure and temperature. Hydrogen uptake was complete in 1 h. The catalyst was filtered off (Hyflo), washed with ethyl acetate (400 ml), the solvent evaporated and the title compound obtained as a cream solid (3.3 g), m.p. 151°-2°. The catalyst was filtered off (Hyflo) washed with ethyl acetate (400 ml) the solvent evaporated