反应详情

A solution of carbamate (6) (41.0 g, 115 mmol) in EtOH (500 mL) was degassed by applying vacuum once. Pd/C (10% wt, 20.0 g) was added and the mixture was degassed by alternating vacuum/H2 three times. The reaction mixture was stirred under H2 pressure of 50 psi for 4 h. The reaction mixture was filtered through Celite, the filtrate was concentrated in vacuum and the residue was purified by crystallization (10% EtOAc in hexane) to give (R)-tert-butyl 3-hydroxy-3-(3-hydroxyphenyl)propylcarbamate (Intermediate I) as a white solid. Yield (24.0 g, 78%); 1H NMR (400 MHz, DMSO-d6) δ 9.25 (s, 1H), 7.07 (t, J=7.6 Hz, 1H), 6.75-6.69 (m, 3H), 6.59 (d, J=8.0 Hz, 1H), 5.11 (d, J=4.0 Hz, 1H), 4.46-4.42 (m, 1H), 2.96 (t, J=6.8 Hz, 2H), 1.66-1.61 (m, 2H), 1.36 (s, 9H); RP-HPLC: tR=1.51 min, 98.13% (AUC); ESI MS m/z 266.28[M−H]+; Chiral HPLC 97.5% (R)-isomer.

1. customthe mixture was degassed
2. filtrationThe reaction mixture was filtered through Celite
3. concentrationthe filtrate was concentrated in vacuum
4. customthe residue was purified by crystallization (10% EtOAc in hexane)