反应详情

温度

67 °C

LiAlH4 (7.9 g, 208 mmol) was added to about 250 ml of THF under a blanket of argon. Diethyl 2-(2′,5′-dimethylphenyl)terephthalate (48.6 g, 149 mmol) (cf. C3) was diluted in a dropping funnel with about 60 ml of THF and was slowly added dropwise. The reaction mixture was vigorously stirred during this addition. The mixture was diluted with a further 100 ml of THF and was then refluxed at 67° C. After 2 hours, the mixture was cooled to RT. While cooling on a water bath and under a blanket of argon, ice water was added dropwise until gas evolution had ceased. Dilute (10% strength) sulfuric acid was subsequently added dropwise until the turbid gray mixture became clear. The phase mixture was separated by generous addition of chloroform and the aqueous phase was subsequently shaken twice with chloroform. The organic phases were shaken once with H2O and evaporated. The crude product was recrystallized from chloroform/hexane: 24.7 g (68%) of colorless, microcrystalline powder; melting point: 145-148° C. (purity>95%).

1. additionwas slowly added dropwise
2. temperaturethe mixture was cooled to RT
3. additionwas added dropwise until gas evolution
4. additionwas subsequently added dropwise until the turbid gray mixture
5. customThe phase mixture was separated by generous addition of chloroform
6. stirringthe aqueous phase was subsequently shaken twice with chloroform
7. stirringThe organic phases were shaken once with H2O
8. customevaporated
9. customThe crude product was recrystallized from chloroform/hexane