反应详情

g (3.39 mmol) of 2-methyl-6-(4-trifluoromethyl-phenyl)-nicotinic acid methyl ester in 7 ml of abs. THF were cooled down to 0° C. and reacted with 7.06 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=7/3) to deliver 0.875 g of the title compound as off-white solid, mp. 76–78° C.

1. customCareful quenching with ice/NH4Cl, twofold extraction with AcOEt
2. washwashing with brine
3. dry with materialdrying over sodium sulfate, and evaporation of the solvents
4. waitleft a crude product which
5. customwas purified by flash chromatography (SiO2, hexane/AcOEt=7/3)