[F-].[K+].C[Si](C)(C)[C:5]([F:8])([F:7])[F:6].[Cl:11][C:12]1[N:19]=[C:18]([Cl:20])[C:17](I)=[CH:16][C:13]=1[C:14]#[N:15].N>CN(C=O)C.[Cu]I.C1COCC1>[Cl:11][C:12]1[N:19]=[C:18]([Cl:20])[C:17]([C:5]([F:8])([F:7])[F:6])=[CH:16][C:13]=1[C:14]#[N:15]
KF (1.95 g, 33.5 mmol) and CuI (6.40 g, 33.5 mmol) were weighed in a flask, and the mixture was heated with a gas burner while gently shaking under high vacuum until the content becomes a pale-yellow green. After cooling to room temperature, anhydrous DMF (50 ml), anhydrous THF (20 ml) and trimethyl (trifluoromethyl)silane (4.80 g, 33.5 mmol) were added. The mixture was heated to 50° C., and stirred for 21 hrs. A mixed solution of Compound 2,6-dichloro-5-iodonicotinonitrile (5.00 g, 16.7 mmol) in anhydrous DMF (10 ml) anhydrous THF (20 ml) was added dropwise to the above mentioned reaction mixture at 50° C. and stirred for 30 hrs. The reaction mixture was cooled to room temperature, poured into 12% aqueous ammonia, and the mixture was extracted EtOAc. The combined organic layer was concentrated in vacuo and the residue was purified by flash chromatography on silica to afford Compound 2,6-dichloro-5-(trifluoromethyl)nicotinonitrile. (1.5 g, yield: 37.5%). 1H-NMR (400 MHz, DMSO-d6) δ (ppm) 9.12 (s, 1H).
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