[CH:1]([C:3]1[CH:4]=[CH:5][C:6]([C:9]#[N:10])=[N:7][CH:8]=1)=[O:2].C[Si](C)(C)[C:13]([F:16])([F:15])[F:14]>C1COCC1>[F:14][C:13]([F:16])([F:15])[CH:1]([C:3]1[CH:4]=[CH:5][C:6]([C:9]#[N:10])=[N:7][CH:8]=1)[OH:2]To a −78° C. solution of 5-formylpicolinonitrile (1.0 g, 7.58 mmol) and tetrabutylammonium triphenyldifluorosilicate (4.9 g, 9.10 mmol) in 60 mL of THF was added a solution of trimethyl(trifluoromethyl)silane (1.62 g, 114 mmol). The mixture was stirred for 20 min at −78° C. Then the cooling bath was changed to an ice bath. After stirring for another 30 min, the reaction was quenched with sat. NH4Cl (aq.). The mixture was extracted with EtOAc (3×). The organic layer was washed with sat. NaHCO3 (aq.), brine, then dried (MgSO4) and concentrated. The product 5-(2,2,2-trifluoro-1-hydroxyethyl)picolinonitrile (600 mg) was obtained by silica gel chromatography (elution with 0-40% EtOAc/Hex).
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