4-Fluorobenzaldehyde → (E)-Methyl 5-fluoro-2-(3-(4-fluorophenyl)-2-(1-methyl-1H-1,2,4-triazol-5-yl)acryloyl)-3-nitrobenzoate

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of methyl 5-fluoro-2-(2-(1-methyl-1H-1,2,4-triazol-5-yl)acetyl)-3-nitrobenzoate (4) (580 mg, 2 mmol) and 4-fluorobenzaldehyde (488 mg, 4 mmol) in dimethylsulfoxide (2 mL) was added L-proline (230 mg, 2 mmol). The resulting mixture was kept with stirring at 45° C. for 48 hours. The reaction system was then partitioned between ethyl acetate (50 mL) and water (30 mL), and the organic phase was washed with water (20 mL×3), dried with Na2SO4, concentrated in vacuo, and purified by column chromatography (ethyl acetate:petroleum ether=1:3) to give the title compound (9) as a pale yellow foam (340 mg, yield 40%). LC-MS (ESI) m/z: 429 (M+1)+. 1H-NMR (400 MHz, DMSO-d6); δ (ppm): 3.56 (s, 3H), 3.86 (s, 3H), 7.02 (dd, 2H), 7.21 (dd, 2H), 7.90 (s, 1H), 8.08 (s, 1H), 8.26 (dd, 1H), 8.56 (dd, 1H).

Provenance & Evidence