反应详情

(S)-6,7-Dihydroxy-1,2,3,4-tetrahydro-isoquinoline-3-carboxylic acid (62 g), 200 mL anhydrous MeOH, and 26 mL concentrated hydrochloric acid were stirred together overnight at 70° C. The mixture was then evaporated and the residue resuspended in 500 mL acetonitrile with vigorous stirring to wash all the solid material. Stirring continued for 18 h at r.t., after which the solid product was collected by filtration, washed with 100 mL acetonitrile, and dried under vacuum overnight. Yield 77 g (quantitative). 1H NMR (400 MHz, MeOH-d4): 6.64 (s, 1H), 6.61 (s, 1H), 4.42-4.36 (m, 1H), 4.29-4.24 (m, 2H), 3.89 (s, 3H), 3.29-3.22 (m, 1H), 3.11-3.02 (m, 1H).

1. customThe mixture was then evaporated
2. washto wash all the solid material
3. stirringStirring
4. filtrationafter which the solid product was collected by filtration
5. washwashed with 100 mL acetonitrile
6. customdried under vacuum overnight