GENERAL METHOD: 3-Aminobut-2-enenenitrile (10 mmol) was added to a suspension of (2-(trifluoromethyl)phenyl)hydrazine (10 mmol) in 12 M HCl-H2O (12 mL, 1:3 v/v). The reaction mixture was heated to reflux for 12 h, subsequently cooled to room temperature and neutralized with 2.5 M NaOH solution. The reaction mixture was extracted with dichloromethane (3 x 30 mL). The organic phases were combined, washed with saturated saline (20 mL), dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was ground with hexane to give a solid product, which was separated by filtration. If necessary, the product was purified by column chromatography.
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