Dimethylformamide → Ethyl 6-cyano-1,2-dihydro-2-(trifluoromethyl)-3-quinolinecarboxylate

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Reaction Conditions

Reaction Steps

N,N-Dimethylformamide (5 mL) was degassed with nitrogen for thirty minutes in a three neck round bottom flask equipped with a condenser, temperature monitoring, nitrogen purge and heating mantle. Ethyl 6-iodo-1,2-dihydro-2-(trifluoromethyl)-3-quinolinecarboxylate (Example 158) (0.522 g, 1.32 mmol) and zinc cyanide (0.102 g, 0.792 mmol) were added to the N,N-dimethylformamide and stirred vigorously for ten minutes. Tetrakis(triphenyl-phosphine)palladium(0) (0.068 g, 0.53 mmol) was added and the contents gently warmed to 80° C. for 2 hours under a nitrogen atmosphere. Ethyl acetate (20 mL) was added, followed by extraction with aqueous 2 N ammonium hydroxide (2×10 mL), water (2×10 mL), saturated ammonium chloride (2×10 mL), dried over sodium sulfate and solvent removed in vacuo to yield a yellow solid. The product was purified by flash chromatography (silica gel, ethyl acetate-hexanes, 3:1) to yield, upon concentration of the appropriate fractions, ethyl 6-cyano-1,2-dihydro-2-(trifluoromethyl)-3-quinolinecarboxylate as a yellow solid (188 mg, 48%): mp 211–212° C. 1H NMR (CDCl3/300 MHz) 7.68 (s, 1H), 7.43 (m, 2H), 6.69 (d, 1H, J=8.3 Hz), 5.22 (m, 1H), 4.98 (br s, 1H), 1.30 (m, 2H), 1.36 (t, 3H, J=7.1 Hz). EIHRMS m/z 314.1147 (M+NH4+, Calc'd 314.1116). Anal. Calc'd for C14H11F3N2O2: C, 56.76; H. 3.74; N, 9.46. Found: C, 56.44; H, 4.03; N, 9.29.

Provenance & Evidence