Diethyl Ether → 2-[(2S)-Piperidin-2-yl]ethan-1-ol

Thus, a mixture of R and S enantiomers of piperidine-2-ethanol obtained from Acros and used as received (127 g, 980 mmol) was dissolved in 95% EtOH (260 mL). To the aliphatic alcohol solution was added to (S)-(+)-camphorsulfonic acid obtained from Acros (228.7 g, 1.0 eq.) in 95% EtOH (150 mL) and the resulting solution was warmed to reflux. To the warm solution was added Et2O (600 mL) and the solution cooled to room temperature and let stand 3 days. The resulting crystals were filtered and dried in vacuo (25 g): and analyzed by mp 173° C. (lit. 168° C.). The salt was then dissolved in NaOH (3M, 100 mL) and stirred 2 hours and the resulting solution was extracted with CH2Cl2 (5×100 mL). The combined organics were dried over Na2SO4, filtered and concentrated under reduced pressure to give (S)-piperidine-2-ethanol (7.8 g) a portion of which was recrystallized from Et2O: mp=69-70° C. (lit. 68-69° C.); [α]D=14.09° (CHCl3, c=0.2). Overall yield of S-isomer isolated, based on initial weight of starting alcohol was 6.1%.

1. temperaturethe resulting solution was warmed to reflux
2. filtrationThe resulting crystals were filtered
3. customdried in vacuo (25 g)
4. customanalyzed by mp 173° C. (lit. 168° C.)
5. dissolutionThe salt was then dissolved in NaOH (3M, 100 mL)
6. extractionthe resulting solution was extracted with CH2Cl2 (5×100 mL)
7. dry with materialThe combined organics were dried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure

ORD record

ord-5027cac520b14b4587810846aa215c69

Source dataset

uspto-grants-2010_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07786306B2