[Li+].CC([N-]C(C)C)C.[F:9][C:10]1[CH:15]=[CH:14][CH:13]=[CH:12][N:11]=1.[CH:16](=[O:19])[CH2:17][CH3:18].[Cl-].[NH4+]>C1COCC1>[F:9][C:10]1[C:15]([CH:16]([OH:19])[CH2:17][CH3:18])=[CH:14][CH:13]=[CH:12][N:11]=1A freshly prepared LDA solution (68.0 mmol) in 500 ml of THF is cooled to −75° C., and 6.00 g (61.8 mmol) of 2-fluoropyridine are added. The mixture is left to stir at this temperature for 2 h, in the course of which a suspension forms. Thereafter, 4.31 g (74.2 mmol) of propanal are added, in the course of which the internal temperature rises to −45° C. After 2 h, the mixture is allowed to come to RT, poured onto saturated ammonium chloride solution and extracted three times with tert-butyl methyl ether. The combined organic phases are washed with sodium chloride solution, dried over sodium sulfate and concentrated. They are purified by chromatography on silica gel (eluent: dichloromethane, then dichloromethane/methanol=25:1). This affords 8.00 g (76% of theory) of the title compound.
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