Triethyl phosphonoacetate → (E)-Ethyl 3-phenyl-3-(pyridazin-4-yl)acrylate

Participants

Reaction Conditions

Reaction Steps

To a solution of ethyl 2-(diethoxyphosphoryl)acetate (1.46 g, 7.93 mmol) in THF (40 mL) was added NaH (476 mg, 11.9 mmol) in portions at 0° C., the resulting mixture was stirred at 0° C. for 20 minutes, then, the phenyl(pyridazin-4-yl)methanone was added in portions, the resulting mixture was stirred at 0° C. for 4 hour. The LC-MS showed the MS signal of desired product was detected, then, the reaction solution was added sat. aq. NH4Cl at 0° C., then, extracted with AcOEt (3×50 ml), the combined organic layers were washed with brine, dried over Na2SO4 and concentrated to get the crude product, which was purified by column chromatography on silica gel (petroleum Ether: EtOAc=2:1) to afford (E)-ethyl 3-phenyl-3-(pyridazin-4-yl)acrylate (1.68 g, yield: 83.2%). 1H NMR (CDCl3 400 MHz): δ9.25 (d, J=5.2 Hz, 1H), 9.06 (s, 1H), 7.47-7.32 (m, 4H), 7.30-7.20 (m, 2H), 6.55 (s, 1H), 4.95 (q, J=7.2 Hz, 2H), 1.16 (t, J=7.2 Hz, 3H).

Provenance & Evidence