Hydrochloric Acid → Octyl Maleimide

Temperature

30 °C

To a suspension of maleic anhydride (3.0 g, 30.6 mmol) in 80 mL of benzene, a solution of octylamine (3.59 g, 27.8 mmol) in 50 mL of benzene was added. The resulting mixture was stirred at 30° C. for an hour and zinc bromide (ZnBr2, 6.89 g, 30.6 mmol) and hexamethyl disilazane (6.72 g, 41.7 mmol) in 20 mL of benzene were added. The resulting suspension was heated under reflux for 2 hours. After cooling to room temperature, the reaction mixture was poured into 200 mL of 0.5 M hydrochloric acid (HCl). The organic layer was separated and the aqueous portion was extracted twice with 150 mL portions of ethyl acetate (EtOAc). The combined organic layers were washed with saturated aqueous sodium bicarbonate (NaHCO3, 2×150 mL), brine (1×150 mL), and dried over magnesium sulfate (MgSO4). The solution was concentrated under vacuum to yield a viscous solid, which is subsequently sublimed to produce N-octylmaleimide as a white solid (4.8 g, 92%). 1H NMR (400 MHz, CDCl3): δ 0.87 (t, 3H, J=6 Hz), 1.20-1.40 (m, 10H), 1.50-1.70 (m, 2H), 3.51 (t, 2H, J=6 Hz), 6.69 (s, 2H).

1. temperatureThe resulting suspension was heated
2. temperatureunder reflux for 2 hours
3. temperatureAfter cooling to room temperature
4. customThe organic layer was separated
5. extractionthe aqueous portion was extracted twice with 150 mL portions of ethyl acetate (EtOAc)
6. washThe combined organic layers were washed with saturated aqueous sodium bicarbonate (NaHCO3, 2×150 mL), brine (1×150 mL)
7. dry with materialdried over magnesium sulfate (MgSO4)
8. concentrationThe solution was concentrated under vacuum
9. customto yield a viscous solid, which

ORD record

ord-6f1ad229ab0a4cdabf4b1b76bd2074c0

Source dataset

uspto-grants-2011_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07892454B2