Reaction #5816

Reaction equation

sodium bicarbonate

amorphous compound

6,7-Dibenzyloxy-2-(5-Isoquinolinesulfonyl)-3-[(4-Phenylpiperazinyl)Methyl]-1,2,3,4-Tetrahydroisoquinoline

1,2-ethanedithiol

boron trifluoride ethyl ether

→

title compound

Yield 90.9%

6,7-Dihydroxy-2-(5-Isoquinolinesulfonyl)-3-[(4-Phenylpiperazinyl)methyl]-1,2,3,4-tetrahydroisoquinoline

Yield 90.9%

Conditions

Workup

1. 1
   Extractionthe reaction mixture was extracted twice with a mixture of chloroform and methanol (1:1)
2. 2
   Dryingthe extract was dried over magnesium sulfate
3. 3
   Concentrationconcentrated under a reduced pressure
4. 4
   Otherto obtain a residue, which
5. 5
   Washeluted with chloroform/methanol (50:1 to 20:1)

Procedure

To 314 mg of the amorphous compound obtained in Example 9, were added 2 ml of 1,2-ethanedithiol and 1 ml of boron trifluoride/ethyl ether, and the mixture was stirred at a room temperature for 18 hours. After the addition of saturated sodium bicarbonate aqueous solution, the reaction mixture was extracted twice with a mixture of chloroform and methanol (1:1), and the extract was dried over magnesium sulfate and concentrated under a reduced pressure to obtain a residue, which was then applied to a silica gel column and eluted with chloroform/methanol (50:1 to 20:1) to obtain 213 mg of the title compound in a colorless amorphous form.

Source