Phosphorus oxychloride → 6,7-Bis-benzyloxy-1-biphenyl-4-ylmethyl-1,2,3,4-tetrahydroisoquinoline hydrochloride

6,7-bis-benzyloxy-1-biphenyl-4-ylmethyl-1,2,3,4-tetrahydro-isoquinoline hydrochloride (2) was prepared as follows: A stirred solution of 3 g (5.69 mmol) of 2-biphenyl-4-yl-N-[2-(3,4-bis-benzyloxy-phenyl)-ethyl]-acetamide and 5.6 ml (60 mmol) of phosphorus oxychloride in 25 ml of anhydrous acetonitrile was refluxed for 20 hours. The reaction solution was evaporated under reduced pressure and the residue was dissolved in 25 ml of methanol. To this stirred solution at 0° C., 2.27 g (60 mmol) of sodium borohydride was added portionwise. The stirred reaction mixture was allowed to reach room temperature overnight and then it was poured in 150 ml of 10% aqueous HCl solution. The precipitate was collected on a glass filter funnel, washed with water (3×50 ml), and air-dried overnight. The solid was recrystallized using ether/methanol mixture to provide 2.56 g (82%) of off-white crystals, mp 187-189° C.

1. customThe reaction solution was evaporated under reduced pressure
2. dissolutionthe residue was dissolved in 25 ml of methanol
3. customThe stirred reaction mixture
4. customThe precipitate was collected on a glass
5. filtrationfilter funnel
6. washwashed with water (3×50 ml)
7. customair-dried overnight
8. customThe solid was recrystallized

ORD record

ord-c2facd33e9a344f89bb695b2f092ee32

Source dataset

uspto-grants-2007_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07241774B2