Hydrochloric Acid → 1-[2-(4-Fluorophenyl)ethyl]-4-ethyl-2,6-dioxopiperidine-3-carbonitrile

Participants

Reaction Conditions

Reaction Steps

A solution of trans 2-pentenoic acid [2-(4-fluorophenyl)ethyl]amide (2.0 g, 9.05 mmol) and ethyl cyanoacetate (1.93 mL, 18.1 mmol) in tert-butanol (30 mL) was treated with a solution of potassium tert-butoxide in tetrahydrofuran (1.0 M, 18.1 mL, 18.1 mmol) and heated at 80° C. After 18 hours, the solution was cooled to room temperature and treated with 1.0 N aqueous hydrochloric acid. The mixture was concentrated under vacuum and the residue was recrystallized from ethanol to provide a pale pink solid (2.0 g, 77%). 1H NMR (300 MHz, CDCl3) δ7.19 (m, 2H), 7.00 (t, J=9 Hz, 2H), 4.01 (m, 2H), 3.50 (d, J=11 Hz, 1H), 2.97 (dd, J=17, 3 Hz, 1H), 2.83 (t, J=8 Hz, 2H), 2.4-2.2 (m, 2H), 1.88 (m, 1H), 1.44 (m, 1H), 1.02 (t, J=7 Hz, 3H). Mass spec (ES−) m/z 287.2 (M+H+, 100%).

Provenance & Evidence