A suspension of 3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-5-nitro-benzoic acid methyl ester (456.0 g, 1.008 mol) in a mixture of methanol (4.5 L), tetrahydrofuran (4.5 L) and water (1.13 L) was treated with allylamine (441.89 ml, 336.25 g, 5.88 mol) and stirred at room temperature for 30 min. (completion of reaction was confirmed by TLC-DCM:MeOH/9:1). The yellow colored suspension was filtered and washed with hexane to remove unreacted allylamine and dried to give the title compound as solid (yellow). Yield: 350g (50.90%), mp. 153–154° C.
