[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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