[Cl:1][C:2]1[CH:7]=[C:6]([C:8]([F:11])([F:10])[F:9])[CH:5]=[C:4]([Cl:12])[C:3]=1[NH:13]C1C=CC=CC=1.[N:20]([O-])=O.[Na+].N>C(O)(=O)C.S(=O)(=O)(O)O.Cl>[Cl:1][C:2]1[CH:7]=[C:6]([C:8]([F:11])([F:10])[F:9])[CH:5]=[C:4]([Cl:12])[C:3]=1[NH:13][NH2:20]2,6-Dichloro-4-trifluoromethylphenylaniline (4.3 g) (described in U.S. Pat. No. 3,850,955) was dissolved, with stirring, in glacial acetic acid (23 ml). A solution of sodium nitrite (1.5 g) in concentrated sulphuric acid (11 ml) was then added at 55°-60° C. The solution thus obtained was cooled to 0°-5° C. and a solution of stannous chloride (16.4 g) in concentrated hydrochloric acid (14 ml) was added with vigorous stirring. A cream-coloured solid precipitated. The mixture was filtered and the solid obtained was added to a mixture of aqueous ammonia solution and ice. The mixture thus obtained was extracted with diethyl ether (×500 ml) and the combined ethereal extracts were dried over sodium sulphate, filtered and evaporated to dryness to give 2,6-dichloro-4-trifluoromethylphenylhydrazine (3.7 g), m.p. 54°-56° C., in the form of a colourless crystalline solid.
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