Yield:23530-42-9 96%

Reaction Conditions:

with triethylamine in dichloromethane;

Steps:

R.4.A N-isopropyl-2-nitrobenzenesulfonamide

Step A N-isopropyl-2-nitrobenzenesulfonamide Isopropylamine (11.07 g, 68.85 mmol) and triethylamine (13 ml, 93 mmol) were dissolved in dichloromethane (50 ml) and the mixture was stirred under ice-cooling. Thereto was added 2-nitrobenzenesulfonyl chloride (10.11 g, 45.62 mmol), and the mixture was stirred at room temperature for 6 hr. The reaction mixture was diluted with ethyl acetate-hexane=1:1 mixed solvent, and the organic layer was washed with diluted hydrochloric acid and water, and dried over anhydrous magnesium sulfate. The insoluble material was filtered off, the solution was concentrated under reduced pressure and the obtained solid was washed with hexane and air-dried to give the title compound (10.73 g, yield 96%) as a colorless solid. ¹H-NMR (300 MHz, CDCl₃); δ(ppm) 1.16 (d, J=6.2, 6H), 3.60-3.73 (m, 1H), 5.12 (d, J=7.1, 1H), 7.72-7.78 (m, 2H), 7.85-7.89 (m, 1H), 8.16-8.20 (m, 1H).

References:

US2012/196824,2012,A1