[F:1][C:2]([F:10])([C:6]([F:9])([F:8])[F:7])[CH:3]([OH:5])[CH3:4].[H-].[Na+].Cl[C:14]1[CH:15]=[CH:16][C:17]([C:20]#[N:21])=[N:18][CH:19]=1.C([O-])([O-])=O.[Na+].[Na+]>CN(C)P(N(C)C)(N(C)C)=O>[F:1][C:2]([CH:3]([O:5][C:15]1[CH:14]=[CH:19][N:18]=[C:17]([C:20]#[N:21])[CH:16]=1)[CH3:4])([F:10])[C:6]([F:9])([F:8])[F:7]Add (±)-3,3,4,4,4-pentafluoro-2-butanol (710 mg, 4.3 mmol) slowly to a slurry of sodium hydride (104 mg, 1.2 equiv, 60% mineral oil, washed with hexane) in hexamethylphosphoramide (2 mL) under nitrogen at 0° C. Allow the slurry to warm to ambient temperature and stir for 5 min. Add 5-chloro-pyridine-2-carbonitrile (300 mg, 2.2 mmol), then heat the mixture in a sealed flask at 130° C. for 4 h (monitor reaction by GC/MS). Cool the reaction to room temperature, adjust the mixture to pH 9 with saturated aqueous Na2CO3, then extract with diethyl ether (2×50 mL). Dry the combined organic extracts over Na2SO4, filter and concentrate in vacuo. Purify the crude mixture by chromatography on silica gel eluting with hexane/EtOAc (19:1 to 7:3 gradient) to obtain the desired intermediate (380 mg, 66%). GC-MS m/z: 266 (M+).
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