Stearyl Alcohol → Octadecyl DI-tert-butyl-4-hydroxyhydrocinnamate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

In a reactor fitted with a heating/cooling bath, stirrer, thermocouple, nitrogen inlet, a reflux condenser with a trap to collect distilled off methanol, and a vacuum connection are added 438.6 g (1.5 moles, a 5% excess) of methyl 3,5-di-tert-butyl-4-hydroxyhydrocinnamate and 386.8 g (1.43 moles) of 1-octadecanol. The mixture is heated to 100° C. under nitrogen with stirring. After drying at 100° C. under vacuum (≤5 mm Hg) for 30 minutes, the mixture is heated to 120° C. under nitrogen and 0.05 g (0.0002 mole) of dibutyltin oxide (Fascat® 4201, Elf-Atochem) is added. The vacuum is lowered to 100 mm Hg and the reaction mixture is heated to 185° C. for one hour. The vacuum is slowly lowered to 2 mm Hg over 1.5 hours and kept at that temperature and pressure for another thirty minutes. The vacuum is broken with nitrogen and the reaction mass is cooled to 100° C. The excess methyl 3,5-di-tert-butyl-4-hydroxyhydrocinnamate is removed using a wiped-film evaporator to give the title compound as a white solid containing 30 ppm Sn. Essentially a quantitative yield (99.8) of the ester product is obtained.

Herkunft & Nachweise