Acetic Acid → 2-[1-(4-Nitrophenyl)ethylidene]malononitrile

Beteiligte Stoffe

Reaktionsschritte

4Nitro acetophenone (2.0 g, 12.1 mmoles, 1 eq) and malonodinitrile (2.4 g, 36.3 mmoles, 3 eq) were dissolved in 20 mL of anhydrous toluene. To the solution were added glacial acetic acid (0.40 mL, 7.0 mmoles, 0.19 eq) and ammonium acetate (0.26 g, 3.3 mmoles, 0.09 eq). The system was heated to reflux using a Dean-Stark trap and a condenser. After 1 hour, the reaction mixture was cooled to room temperature and poured into brine (50 mL) and ethyl acetate (100 mL). The aqueous layer was washed with 3×10 mL ethyl acetate. The combined organic layers were washed with 50 mL brine, dried over anhydrous sodium sulfate and concentrated to dryness. The dark residue was partially purified using a silica plug (40% ethyl acetate-hexane) affording crude 1,1-dicyano-2-(4-nitrophenyl)-propene. The product was used as such in the next step. TLC (40% ethyl acetate-hexane)=0.61. LC-MS (m/e)=214.2 (MH+).

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