Methanol → 1-Aminomethyl-5,6-dihydroxy-3-phenyl-3,4-dihydronaphthalene Hydrobromide

HRID 1089010Notes

Reaction equation

HRID 1089010 reaction equation
Cl.[NH2:2][CH2:3][C:4]1[C:13]2[C:8](=[C:9]([O:16]C)[C:10]([O:14]C)=[CH:11][CH:12]=2)[CH2:7][CH:6]([C:18]2[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=2)[CH:5]=1.B(Br)(Br)[Br:25].CO>C(Cl)Cl>[BrH:25].[NH2:2][CH2:3][C:4]1[C:13]2[C:8](=[C:9]([OH:16])[C:10]([OH:14])=[CH:11][CH:12]=2)[CH2:7][CH:6]([C:18]2[CH:19]=[CH:20][CH:21]=[CH:22][CH:23]=2)[CH:5]=1

Participants

5

Reactant 3

HCID 887MethanolHCID 25134Boron tribromideHCID 19961156HCID 19961156, compound

Product 1

HCID 199611231-Aminomethyl-5,6-dihydroxy-3-phenyl-3,4-dihydronaphthalene HydrobromideYield 45%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Conditions

Temperature
-78 °C

Procedure

1-Aminomethyl-3,4-dihydro-5,6-dimethoxy-3-phenyl-naphthalene hydrochloride (6.0 g, 20.2 mmol), from Step 2, was suspended in 200 mL of methylene chloride and boron tribromide (90.5 mL of 1M solution of BBr3 in methylene chloride) was added dropwise while the reaction mixture was being cooled (to -78° C.) in a dry ice/acetone bath. The reaction mixture was warmed to 0° C. and stirred for 0.5 h, then again cooled to -78° C. in a dry ice/acetone bath. Methanol (50 mL) was added dropwise to the reaction mixture, which was allowed to warm to ambient temperature then concentrated in vacuo. Methanol was added to the residue and the solution was reconcentrated. This residue was dissolved in a small amount of methanol and the methanol solution was aded to 700 mL of diethyl ether. The precipitate which formed was filtered, washed with diethyl ether and recrystallized from methanol/ether to give 2.5 g (45% yield) of 1-aminomethyl-3,4-dihydro-5,6-dihydroxy-3 -phenyl-naphthalene hydrobromide, m.p. 223°-225° C. 1H NMR (d6DMSO) delta 2.68 (dd, 1H), 3.09 (dd, 1H), 3.6-3.7 (m, 1H), 3.9 (s, 2H), 5.97 (d, 1H), 6.69 (m, 2H), 7.2-7.35 (m, 5H), 8.1 (br s, 3H), 8.4 (s, 1H), 9.5 (s, 1H).

Workup

  1. temperatureThe reaction mixture was warmed to 0° C.
  2. temperatureagain cooled to -78° C. in a dry ice/acetone bath
  3. temperatureto warm to ambient temperature
  4. concentrationthen concentrated in vacuo
  5. additionMethanol was added to the residue
  6. dissolutionThis residue was dissolved in a small amount of methanol
  7. customThe precipitate which formed
  8. filtrationwas filtered
  9. washwashed with diethyl ether
  10. customrecrystallized from methanol/ether

Sources & evidence

ORD record
ord-1489377aa6ef43b2bb5346ea454c5306
Source dataset
uspto-grants-1990_10
Patent number
US04963568

Reaction notes

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