Methanol → HCID 19961204, compound

[1 R, 3 S]1-Aminomethyl-3-cyclohexyl-5,6-dimethoxy-1,2,3,4-tetrahydronaphthalene hydrochloride (0.7 g, 2.3 mmol), from Step 1, was suspended in 20 mL of methylene chloride at -78° C. Boron tribromide (9.7 mL of a 1M solution in methylene chloride, 9.7 mmol) was added and the reaction mixture was allowed to warm to ambient temperature. After stirring at ambient temperature for 1 h, the reaction mixture was cooled to -78° C. and 10 mL of methanol was added. The reaction mixture was again allowed to warm to ambient temperature and stirred at ambient temperature for 1 h. The solvent was removed in vacuo and methanol was added to the residue. The methanol solution was concentrated and the residue dissolved in a minimal amount of methanol and added dropwise to a large excess of diethyl ether. The precipitate was filtered and recrystallized from ethanol/diethyl ether to give 0.48 g (65% yield) of [1 R, 3 S]1-aminomethyl-3-cyclohexyl-5,6-dihydroxy-1,2,3,4-tetrahydronaphthalene hydrobromide, m.p. 203°-204° C.: 1H NMR (d6 -DMSO) δ: 0.9-1.5 (m, 8H), 1.6-1.9 (m, 5H), 2.0-2.1 (m, 2H), 2.7-3.0 (m, 3H), 3.3-3.4 (m, 1H), 6.5-6.7 (m, 2H).

1. temperaturethe reaction mixture was cooled to -78° C.
2. temperatureto warm to ambient temperature
3. stirringstirred at ambient temperature for 1 h
4. customThe solvent was removed in vacuo and methanol
5. additionwas added to the residue
6. concentrationThe methanol solution was concentrated
7. dissolutionthe residue dissolved in a minimal amount of methanol
8. additionadded dropwise to a large excess of diethyl ether
9. filtrationThe precipitate was filtered
10. customrecrystallized from ethanol/diethyl ether

ORD record

ord-c1133db2d13f481db65f0b2d32d31526

Source dataset

uspto-grants-1997_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05591884