S(O)(O)(=O)=O.[NH2:6]O.C(=O)([O-])[O-].[K+].[K+].S([O-])([O-])=O.[Na+].[Na+].[OH:20][C:21]1[CH:30]=[CH:29][CH:28]=[C:27]([O:31][CH2:32][C:33]([F:36])([F:35])[F:34])[C:22]=1[C:23](OC)=[O:24]>O>[F:34][C:33]([F:36])([F:35])[CH2:32][O:31][C:27]1[C:22]2[C:23]([OH:24])=[N:6][O:20][C:21]=2[CH:30]=[CH:29][CH:28]=1
To a solution of hydroxylamine sulfate (120 g, 732 mmol) in water (360 mL) was added potassium carbonate (121 g, 875 mmol) at 0° C. After 30 min of stirring, sodium sulfite (3.74 g, 29.7 mmol) and a methanolic solution of methyl 2-hydroxyl-6-(2,2,2-trifluoroethoxy)benzoate (36.4 g, 146 mmol, EXAMPLE 1, step 1, in 360 mL of methanol) were added to the mixture. Then the mixture was warmed to 50° C. and stirred for 30 h. After cooling to room temperature, reaction mixture was partially concentrated to approx. ⅔ volume and acidified with 2N hydrochloric acid. Product was extracted three times with ethyl acetate. Combined organic layer was washed with brine, dried over sodium sulfate and concentrated under reduced pressure to afford the desired product as a crystalline solid. Crude product (36.3 g) was used for the next step without further purification.
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