反应详情

To a solution of 3-amino-5-nitro-benzoic acid methyl ester (D1) (45 g, 229 mmol, 1 equiv) in CH2Cl2 (450 ml) was added pyridine (18.5 ml, 229 mmol, 1 equiv), DMAP (100 mg, 0.8 mmol, catalytic) and 3-chloropropanesulfonyl chloride (28 ml, 230 mmol, 1 equiv). The resulting mixture was stirred for 40 h then diluted with AcOEt. The organic phase was diluted with 2N aqueous HCl solution. The resulting solid was filtered to give 3-(3-chloro-propane-1-sulfonylamino)-5-nitro-benzoic acid methyl ester (23 g, 32%). The filtrate was separated and the organic phase was washed with saturated aqueous NaHCO3 solution, dried over MgSO4 and concentrated in vacuo. The residue was triturated with AcOEt and isohexane to give a further 50 g (65%) of 3-(3-chloro-propane-1-sulfonylamino)-5-nitro-benzoic acid methyl ester (D14) as a pale brown solid. [M−H]−=334.9, RT=3.11 min

1. filtrationThe resulting solid was filtered