1.To a solution of 4-Nitroaniline (1mmol,1equiv) in pyridine 10 ml was added p-toulenesulfonyl chloride (1.1mmol,1.1equiv) at 0 oC2.The mixture was heated to 50~60 oC for 1hr, the pyridine was removed by rotary evaporator and the mixture was poured into water. 3.The product was extract with DCM (10ml X3 ),dried over with MgSO4,and concentrated in vacuo.4.The residue was purified by column with EA/Hexane.