Hydrochloric Acid → 4-[(4-{[(tert-butoxycarbonyl)amino]methyl}piperidin-1-yl)methyl]tetrahydro-2H-pyran-4-carboxylic acid

Temperature

60 °C

To a solution of Methyl 4-[(4-{[(tert-butoxycarbonyl) amino]methyl}piperidin-1-yl) methyl]tetrahydro-2H-pyran-4-carboxylate (6.47 g, 17.5 mmol, Step 10) in MeOH (32 mL), 5 N NaOH aq (10 mL) was added at room temperature (exothermic). The resulting solution was stirred at 60° C. for 7 h, then cooled to 5-10° C. in ice-cold bath. To this solution, 5 N HCl aq (10 mL) was added and the resulting solution (pH value was ca.6) was concentrated. To the residue, 2-propanol (80 mL) was added. This solution was concentrated. To the residue, 2-propanol (80 mL) was added and it was concentrated again. The residue was diluted with EtOH (80 mL) and the mixture was stirred at room temperature for 2 h. It was filtered through a celite pad (5.0 g) to remove NaCl. The Celite pad was washed with EtOH (20 mL) and the combined filtrate was concentrated. To the residue, CH3CN (40 mL) was added and it was concentrated. During this procedure, the formation of white precipitate was noticed. To the residue CH3CN (40 mL) was added and the resulting suspension was stirred at room temperature for 2 h. This mixture was filtered and obtained solid was washed with CH3CN (10 mL), then dried under reduced pressure to give 4.1 g (65%) of the titled compound as white powder.

1. temperaturecooled to 5-10° C. in ice-cold bath
2. concentrationthe resulting solution (pH value was ca.6) was concentrated
3. additionTo the residue, 2-propanol (80 mL) was added
4. concentrationThis solution was concentrated
5. additionTo the residue, 2-propanol (80 mL) was added
6. concentrationit was concentrated again
7. additionThe residue was diluted with EtOH (80 mL)
8. stirringthe mixture was stirred at room temperature for 2 h
9. filtrationIt was filtered through a celite pad (5.0 g)
10. customto remove NaCl
11. washThe Celite pad was washed with EtOH (20 mL)
12. concentrationthe combined filtrate was concentrated
13. additionTo the residue, CH3CN (40 mL) was added
14. concentrationit was concentrated
15. additionTo the residue CH3CN (40 mL) was added
16. stirringthe resulting suspension was stirred at room temperature for 2 h
17. filtrationThis mixture was filtered
18. customobtained solid
19. washwas washed with CH3CN (10 mL)
20. customdried under reduced pressure

ORD record

ord-c314f0b91f764d18819a18f20047512d

Source dataset

uspto-grants-2010_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07705020B2