1,4-Dioxane hydrochloride → 2H-Pyran-4-ol, 4-[[4-(aminomethyl)-1-piperidinyl]methyl]tetrahydro-

To a solution of tert-butyl ({1-[(4-hydroxytetrahydro-2H-pyran-4-yl)methyl]piperidin-4-yl}methyl)carbamate as prepared in 1(3) (50.28 g, 153 mmol) in methanol (100 mL) was added 4N hydrochloric acid dioxane solution (200 mL, 800 mmol) at room temperature. After 4 h, the volatile materials were removed by evaporation. The resulting amorphous was precipitated with diethyl ether/methanol (v/v=5/1). The precipitate was collected and added to the ice cooled 6N aqueous sodium hydroxide solution (200 mL) gradually. The mixture was extracted with dichloromethane/methanol (v/v=10/1, 500 mL×4). The combined organic layers were washed with brine, dried over magnesium sulfate and concentrated in vacuo to give 24.90 g (99%) of the title compound as a pale brown amorphous solid.

1. customthe volatile materials were removed by evaporation
2. customThe resulting amorphous was precipitated with diethyl ether/methanol (v/v=5/1)
3. customThe precipitate was collected
4. additionadded to the ice
5. temperaturecooled 6N aqueous sodium hydroxide solution (200 mL) gradually
6. extractionThe mixture was extracted with dichloromethane/methanol (v/v=10/1, 500 mL×4)
7. washThe combined organic layers were washed with brine
8. dry with materialdried over magnesium sulfate
9. concentrationconcentrated in vacuo

ORD record

ord-3896236e0a324b6eb43effba4eed1824

Source dataset

uspto-grants-2010_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07691881B2