反应详情

Hydrochloride salts of the separated enantiomers were obtained by the following processes. 1.25 g (0.005 mol) of optical isomer 1 (retention time 6.117 min) ((−)-(2R,3R)-2-(3-chlorophenyl)-3,5,5-trimethyl-2-morpholinol) was dissolved in diethyl ether. The solution was filtered and the filtrate was chilled in an ice-bath adding ethereal hydrogen chloride until the solution was acidic. After standing at ambient temperature for 24 h, the resulting solid was filtered, washed with diethyl ether and dried in a vacuum oven at 60° C. for 18 h to give 1.32 g (90%) of (−)-(2R,3R)-2-(3-chlorophenyl)-3,5,5-trimethyl-2-morpholinol hydrochloride as a white solid: mp 208–209° C. NMR (300 Mhz, DMSO-d6); δ 9.72 (br, 1H), 8.76 (br, 1H), 7.54–7.41 (m, 5H), 3.98 (d, 1H), 3.52 (d, 1H), 3.37 (br s, 1H), 1.53 (s, 3H), 1.29 (s, 3H), 0.97 (d, 3H). Anal. Calcd for C13H19Cl2NO2: C, 53.43; H, 6.55; N, 4.79. Found: C, 53.35; H, 6.57; N, 4.71. (α)D20° C.=−33.2° (0.67, 95% EtOH)

1. filtrationThe solution was filtered
2. temperaturethe filtrate was chilled in an ice-bath
3. additionadding ethereal hydrogen chloride until the solution
4. filtrationthe resulting solid was filtered
5. washwashed with diethyl ether
6. customdried in a vacuum oven at 60° C. for 18 h