Step 3: Preparation of 2-(isopropylsulfonyl)aniline (4); 1-(isopropylsulfonyl)-2-nitrobenzene (3, 2 g, 8.73 mmol) was dissolved in methanol (25 ml) to form a homogeneous mixture. 10% palladium carbon (200 mg, 10 mol%) was added to the mixture and the reaction mixture was stirred under hydrogen atmosphere for 6 hours. The progress of the reaction was monitored by thin layer chromatography (TLC) to confirm the complete conversion of feedstock 3 to product 4. Upon completion of the reaction, the mixture was filtered through diatomaceous earth, and the filtrate was concentrated under reduced pressure to afford 2-(isopropylsulfonyl)aniline (4, 1.73 g, quantitative yield).' HNMR (CDCl3): δ 7.66-7.62 (d, 1H), 7.40-7.30 (t, 1H), 6.85-6.78 (t, 1H), 6.73-6.70 (d, 1H), 5.10 (br s, 1H), 3.40-3.30 (m, 1H), 1.30 (s, 6H).
