[CH3:1][O:2][C:3]1[CH:10]=[CH:9][C:8]([F:11])=[C:7]([F:12])[C:4]=1[CH:5]=O.Cl.[NH2:14][OH:15].C([O-])(=O)C.[Na+]>CO>[CH3:1][O:2][C:3]1[CH:10]=[CH:9][C:8]([F:11])=[C:7]([F:12])[C:4]=1[CH:5]=[N:14][OH:15]At 20-25° C., a solution of 29.4 g of 2-methoxy-5,6-difluoro-benzaldehyde (according to Ex. 27 of WO 97/03071) was added dropwise with stirring to a mixture of 16.0 g of hydroxylamine hydrochloride, 18.9 g of sodium acetate and 110 ml of 90% strength aqueous methanol. The mixture was stirred for 16 hours, the methanol was evaporated, the mixture was made into a paste using 250 ml of water and then washed and dried, giving 28.3 g of the desired product of m.p. 199-201° C.
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