反应详情

73.3 g (0.55 mol) of ground aluminium trichloride are added over 25 minutes to a solution of 131.2 g (0.50 mol) of 5,7-di-tert-butyl-3-hydroxy-3H-benzofuran-2-one (compound (201), Table 2, Example 1a) in 250 ml (2.82 mol) of benzene and the reaction mixture is heated for 1.5 hours to reflux temperature and then refluxed for 1.5 hours. The reaction mixture is cooled to room temperature and then, cautiously with cooling, 200 ml of water are added, followed by the addition of concentrated hydrochloric acid until a homogeneous two-phase mixture forms. The organic phase is separated, washed with water, dried over sodium sulfate and concentrated on a vacuum rotary evaporator. Crystallisation of the residue from ethanol yields 97.8 g (64%) of 5,7-di-tert-butyl-3-phenyl-3H-benzofuran-2-one, m.p. 116°-119° C. (compound (108), Table 1).

1. temperaturethe reaction mixture is heated for 1.5 hours
2. temperatureto reflux temperature
3. temperaturerefluxed for 1.5 hours
4. temperaturecautiously with cooling
5. customThe organic phase is separated
6. washwashed with water
7. dry with materialdried over sodium sulfate
8. concentrationconcentrated on a vacuum rotary evaporator
9. customCrystallisation of the residue from ethanol