反应详情

Methyl (±)-4-[α-hydroxy-5-(1-imidazolyl)-2-methylbenzyl]-3,5-dimethylbenzoate (70 g) was suspended in dimethylformamide (350 ml) and pyridine (23.7 ml) and a solution of (S)-2-(6-methoxy-2-naphthyl)propionyl chloride (59.7 g) in toluene (250 ml) was added dropwise to the suspension over 10 minutes with stirring under ice-cooling. The mixture was stirred at room temperature for 4 hours, poured into water (1400 ml), and the precipitated oily substance was extracted with toluene and washed successively with 5% citric acid, 5% potassium carbonate and water. The organic layer was separated and dried over magnesium sulfate. The solvent was evaporated under reduced pressure to give 113 g of methyl (±)-4-[5-(1-imidazolyl)-α-{(S)-2-(6-methoxy-2-naphthyl)propionyloxy}-2-methylbenzyl]-3,5-dimethylbenzoate as pale-yellow oil. This was crystallized from isopropyl alcohol (560 ml), and the obtained crystals were recrystallized from isopropyl alcohol (300 ml) to give 42 g of methyl (S)-4-[5-(1-imidazolyl)-α-{(S)-2-(6-methoxy-2-naphthyl)propionyloxy}-2-methylbenzyl]-3,5-dimethylbenzoate as white crystals, melting point 156-158° C., optical rotation [α]D24 +87.3° (c=1, chloroform).

1. temperaturecooling
2. stirringThe mixture was stirred at room temperature for 4 hours
3. extractionthe precipitated oily substance was extracted with toluene
4. washwashed successively with 5% citric acid, 5% potassium carbonate and water
5. customThe organic layer was separated
6. dry with materialdried over magnesium sulfate
7. customThe solvent was evaporated under reduced pressure