反应详情

5-Hydroxyisophthalic acid (9.11 g, 50.0 mmole) and t-butyldimethylsilyl chloride (25.2 g, 167 mmole) were dissolved in anhydrous N,N-dimethylformamide (55 ml). Upon adding imidazole (20.4 g, 300 mmole), the solution was stirred overnight before shaking with diethyl ether (200 ml) and water (600 ml). The organic layer was reduced in volume by evaporation to a clear oil, which was mixed with tetrahydrofuran (45 ml), water (30 ml), glacial acetic acid (30 ml) and acidified with 37% HCl solution. The reaction mixture was stirred for a couple of hours. Upon evaporating off THF, the solution was shaken with methylene chloride (200 ml) and water (200 ml). The organic was washed twice with water (200 ml each), and the insoluble product was collected by filtration. Additional product was collected by washing with water the solid residue from evaporating off the solvent. A total of 10.1 g (68%) of (a) was obtained with its structure validated by proton NMR spectroscopy.

1. customThe organic layer was reduced in volume by evaporation to a clear oil, which
2. additionwas mixed with tetrahydrofuran (45 ml), water (30 ml), glacial acetic acid (30 ml)
3. stirringThe reaction mixture was stirred for a couple of hours
4. customUpon evaporating off THF
5. stirringthe solution was shaken with methylene chloride (200 ml) and water (200 ml)
6. washThe organic was washed twice with water (200 ml each)
7. filtrationthe insoluble product was collected by filtration
8. customAdditional product was collected
9. washby washing with water the solid residue
10. customfrom evaporating off the solvent