C[O:2][C:3](=O)[C:4]1[CH:9]=[CH:8][C:7]([C:10]2[CH:15]=[CH:14][CH:13]=[C:12]([C:16]([F:19])([F:18])[F:17])[CH:11]=2)=[N:6][C:5]=1[CH3:20].CC(C[AlH]CC(C)C)C>C1COCC1>[CH3:20][C:5]1[C:4]([CH2:3][OH:2])=[CH:9][CH:8]=[C:7]([C:10]2[CH:15]=[CH:14][CH:13]=[C:12]([C:16]([F:18])([F:17])[F:19])[CH:11]=2)[N:6]=11.96 g (6.62 mmol) of the above synthesized 2-methyl-6-(3-trifluoromethyl-phenyl)-nicotinic acid methyl ester in 14 ml of abs. THF was cooled down to 0° C. and reacted with 13.8 ml of DIBAL-H-solution (1.2 M in toluene, 2.5 eq.) for 1 h. Careful quenching with ice/NH4Cl, twofold extraction with AcOEt, washing with brine, drying over sodium sulfate, and evaporation of the solvents left a crude product which was purified by flash chromatography (SiO2, hexane/AcOEt=55/45) to deliver finally 1.66 g of the title compound as white crystals of mp. 75-77° C.
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