Br.[CH2:2]1[C:11]2[C:6](=[CH:7][C:8]([OH:12])=[CH:9][CH:10]=2)[CH2:5][CH2:4][NH:3]1.O.Cl[C:15]([O:17][CH2:18][C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1)=[O:16].C(=O)([O-])[O-].[K+].[K+]>O1CCOCC1>[CH2:18]([O:17][C:15]([N:3]1[CH2:4][CH2:5][C:6]2[C:11](=[CH:10][CH:9]=[C:8]([OH:12])[CH:7]=2)[CH2:2]1)=[O:16])[C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1
A solution of 8.00 g (49 mmol) of 6-Methoxy-1,2,3,4-tetrahydro-isoquinoline in 196 mL of 48% hydrobromic acid was refluxed for 3 h. The mixture was then concentrated and coevaporated several times with ethanol. The resulting slurry was filtered and dried under vacuum to give 7.43 g of 1,2,3,4-Tetrahydro-isoquinolin-6-ol hydrobromide as a solid. To 7.38 g of the crude hydrobromide dissolved in 117 mL each of dioxane and water was added 6.34 g (35.3 mmol) of benzyl chloroformate with ice bath cooling. A 1 M solution of potassium carbonate was slowly added until a pH of 10 was maintained. The mixture was stirred overnight at room temperature. Excess dioxane was removed by evaporation, and the resulting aqueous mixture was acidified with 1 N HCl and the product extracted with ethyl acetate. The organic portion was washed with water and brine, dried over Na2SO4 and concentrated to give 10.4 g of an oil which was crystallized from ether/hexane to give 7.05 g of 7D as a solid.
Loading…
