反应详情

(3S)-6,7-Dihydroxy-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid [J. Org. Chem., 26, 3533 (1961)] (33.9 g) and sodium borate.10H2O (62 g) are suspended in water (500 ml). Benzoyl chloride (27.5 g) and a solution of sodium hydroxide (13 g) in water (100 ml) are added dropwise to the suspension at 0° C. under stirring. The mixture is stirred at room temperature for 4 hours. The mixture is washed with ethyl acetate, and acidified with conc. HCl, and extracted with ethyl acetate. The extract is dried and distilled to remove the solvent. The crystals are collected by filtration, washed with benzene and then recrystallized from water, whereby (3S)-2-benzoyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (41.7 g) is obtained.

1. stirringThe mixture is stirred at room temperature for 4 hours
2. washThe mixture is washed with ethyl acetate
3. extractionextracted with ethyl acetate
4. customThe extract is dried
5. distillationdistilled
6. customto remove the solvent
7. filtrationThe crystals are collected by filtration
8. washwashed with benzene
9. customrecrystallized from water