[F:1][C:2]([F:12])([F:11])[CH:3]([C:5]1[CH:6]=[N:7][CH:8]=[CH:9][CH:10]=1)[OH:4].Cl[O-].[Na+].O>S([O-])(O)(=O)=O.C([N+](CCCC)(CCCC)CCCC)CCC.C(Cl)Cl>[F:12][C:2]([F:1])([F:11])[C:3]([C:5]1[CH:6]=[N:7][CH:8]=[CH:9][CH:10]=1)=[O:4]13.2 g (0.075 mol) of 2,2,2-trifluoro-1-(3-pyridyl)ethanol and 1.26 g (0.0037 mol) of tetrabutylammonium hydrogen sulfate are dissolved in 250 ml of methylene chloride at room temperature. 46 ml (0.09 mol) of an approximately 12% strength sodium hypochlorite solution are metered in within 20 minutes with vigorous stirring and the mixture is stirred for a further 4 hours during which the reaction temperature rises to 35° C. The reaction mixture is added to 250 ml of water, the phases are separated, the aqueous phase is extracted several times with methylene chloride and the combined organic phases are washed with saturated aqueous sodium chloride solution. After drying the organic phase with sodium sulfate, the volatiles are distilled off. Following distillation of the crude product (28 torr, 65°-70°C.), 9.39 g (72% of theory) of 3-trifluoroacetylpyridine are obtained. nD20 : 1.4796.
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