反应详情

3,5-Dimethyl-4-(3'-isopropyl-4'-benzyloxyphenoxy)-nitrobenzene, (2.86 kg, 7.31 mol) is dissolved in a mixture of ethanol/tetrahydrofuran (10:1, 114 L) and cooled to 100. This is admixed with 10% Pd/C (800 g) and the systemis pressurized to 15 psi with hydrogen gas. The hydrogenation is continued for 18 hours. The mixture is then filtered through Celite and the Gelitc is washed with tetrahydrofuran (30 L). The filtrate is then evaporated in vacuo to dryness (50°, 3 Torr). The solid residue is triturated with heptane (3 L) and filtered. The filter cake is washed with heptane (2×500 mL) to obtain crude product which is then dissolved in hot ethyl acetate (14 L) and diluted with heptane (30 L). The product slowly precipitates and the mixture is cooled at 10 for 1 hour, collected by filtration and washed with ethyl acetate/hexane 1:2 (2×500 mL). The filter cake is then dried (60°, 3 Torr for 24 hours to yield 3,5-dimethyl-4-(3'-isopropyl-4'-hydroxyphenoxy)-aniline, m.p. 180°-181°.

1. temperaturecooled to 100
2. filtrationThe mixture is then filtered through Celite
3. washthe Gelitc is washed with tetrahydrofuran (30 L)
4. customThe filtrate is then evaporated in vacuo to dryness (50°, 3 Torr)
5. customThe solid residue is triturated with heptane (3 L)
6. filtrationfiltered
7. washThe filter cake is washed with heptane (2×500 mL)
8. customto obtain crude product which
9. customThe product slowly precipitates
10. temperaturethe mixture is cooled at 10 for 1 hour
11. filtrationcollected by filtration
12. washwashed with ethyl acetate/hexane 1:2 (2×500 mL)
13. customThe filter cake is then dried (60°, 3 Torr for 24 hours