Acetic Acid → Benzyl ((2S,3R)-1-(4-((tert-butyloxycarbonylamino)methyl)phenyl)-3-hydroxy-4-methylpent-4-en-2-yl)carbamate

Participants

Reaction Conditions

Reaction Steps

Ketone 12 (2.81 g, 4.30 mmol) was dissolved in MeOH (25 mL) and cooled to 0° C. To this were added CeCl3.7H2O (1.5 eq., 6.45 mmol, 2.43 g) and NaBH4 (1.4 eq., 6.0 mmol, 227 mg) portion-wise and the mixture was stirred for 5 minutes. after which TLC analysis indicated a complete conversion. Glacial acetic acid (10 mL) was added and the mixture was concentrated under reduced pressure. The resulting residue was dissolved in EtOAc and extracted with half saturated aq. NaHCO3 (2×) and brine, dried over MgSO4 and concentrated in vacuo. The title compound was obtained as a colourless oil (yield: 1.79 g, 3.94 mmol, 92%). 1H NMR (400 MHz, CDCl3): δ=7.31-7.01 (m, 9H), 5.30 (d, J=9.18 Hz, 1H), 5.06 (s, 1H), 5.00 (d, J=5.19 Hz, 1H), 4.96-4.91 (m, 3H), 4.21 (d, J=4.41 Hz, 1H), 4.16-4.11 (m, 1H), 4.07-3.98 (m, 1H), 2.85 (d, J=12.55 Hz, 1H), 2.65 (dd, J=13.60, 10.41 Hz, 1H), 1.77 (s, 3H), 1.44 (s, 9H) ppm. 13C NMR (100 MHz, CDCl3): δ=155.96, 155.85, 144.44, 137.34, 136.44, 129.34, 128.19, 127.77, 127.66, 127.25, 112.17, 79.25, 76.65, 66.27, 54.06, 44.15, 33.69, 28.22, 18.73 ppm. [α]D23=−18.7 (c=1, CHCl3). HRMS: calcd. for C26H34N2O5 455.25405 [M+H]+. Found 455.25392.

Provenance & Evidence