3-Chlorobenzaldehyde → cis-N-[4-(3-chlorophenyl)-but-3-enyl]-phthalimide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirred suspension of (3-(1,3-dioxoisoindolin-2-yl)propyl)triphenylphosphonium bromide (17.6 g, 33.2 mmol) in tetrahydrofuran (170 mL) at ambient temperature was added 3-chlorobenzaldehyde (3.76 mL, 33.2 mmol), and the resulting mixture was cooled with a dry-ice acetone bath to −75° C. Solid potassium t-butoxide (3.72 g, 33.2 mmol) was added, and stirring was continued in the bath for an additional 20 minutes; the temperature was −80° C. The cooling bath was removed, and when the internal temperature reached −30° C., the flask was placed in a water-ice bath. The temperature eventually settled at 10° C. and was maintained for 2 hours. The reaction mixture was poured into a separatory funnel containing water (250 mL), and this was extracted with ethyl acetate (250 mL) The organic layer was dried over sodium sulfate and concentrated. The residue was purified by chromatography on silica gel, eluting with 90/10 hexanes/ethyl acetate, to afford (Z)-2-(4-(3-chlorophenyl)but-3-enyl)isoindoline-1,3-dione as a white solid (8.46 g, 82% yield).

Herkunft & Nachweise