4-Chloro-alpha,alpha,alpha-trifluoro-3-nitrotoluene → 2-Nitro-4-trifluoromethylanisole

Beteiligte Stoffe

Reaktionsschritte

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-trifluoromethylanisole, and reducing this compound to 2-amino-4-trifluoromethylanisole. The latter compound may be diazotised and converted to its fluoborate salt and heated to give 2-fluoro-4-trifluoromethylanisole. This may then be nitrated to form 2-fluoro-6-nitro-4-trifluoromethylanisole, which is then reduced to give 2-amino-6-fluoro-4-trifluoromethylanisole. Finally the latter compound is heated with a demethylating agent, for example an excess of pyridine hydrochloride to give 2-amino-6-fluoro-4-trifluoromethylphenol.

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