N[C:2]1[CH:7]=[C:6]([C:8]([F:11])([F:10])[F:9])[CH:5]=[C:4]([F:12])[C:3]=1[OH:13].[N+]([C:17]1C=C(C(F)(F)F)C=CC=1Cl)([O-])=O.C[O-].[Na+].NC1C=C(C(F)(F)F)C=CC=1OC.F[B-](F)(F)F>>[F:12][C:4]1[CH:5]=[C:6]([C:8]([F:11])([F:10])[F:9])[CH:7]=[CH:2][C:3]=1[O:13][CH3:17]The 2-amino-4-trifluoromethylphenols (XI) required for the reaction sequence just described may be prepared by conventional methods. Thus 2-amino-6-fluoro-4-trifluoromethylphenol may be prepared from 2-nitro-4-trifluoromethylchlorobenzene by reacting the latter with sodium methoxide to give 2-nitro-4-trifluoromethylanilsole, and reducing this compound to 2-amino-4-trifluoromethylanisole. The latter compound may be diazotised and converted to its fluorborate salt and heated to give 2-fluoro-4-trifluoromethylanisole. This may then be nitrated to form 2-fluoro-6-nitro-4-trifluoromethyl anisole, which is then reduced to give 2-amino-6-fluoro-4-trifluoromethylanisole. Finally the latter compound is heated with a dimethylating agent, for example an excess of pyridine hydrochloride to give 2-amino-6-fluoro-4-trifluoromethylphenol.
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