Allyl bromide → (5R,6S)-3-allyl-5-(3-chlorophenyl)-6-(4-chlorophenyl)-1-(2,4-dimethoxybenzyl)-3-methylpiperidin-2-one

Temperatur

40 °C

A solution of (5R,6S)-5-(3-chlorophenyl)-6-(4-chlorophenyl)-1-(2,4-dimethoxybenzyl)-3-methylpiperidin-2-one (Example 71, Step B, mixture of C-3 diastereomers) (117.0 g, 242 mmol) in anhydrous THF (966 mL) was degassed by bubbling argon through the solution for 20 minutes. Allyl bromide (105 mL, 1208 mmol) was added followed by the addition of LHMDS (725 mL, 725 mmol) over 20 minutes. The reaction mixture was heated at 40° C. under argon for 5 hours. The reaction mixture was cooled to rt. and the reaction was quenched by the addition of sat. aqueous NH4Cl (500 mL) and the layers were separated. The aqueous layer was extracted with EtOAc (2×1 L) and the organics were pooled, washed with sat. aq. NaCl solution (1 L), dried (MgSO4), filtered and concentrated in vacuo to provide a red oil (180 g). Purification using the Biotage system (Charlotte, N.C.) with a 1.5 kg SiO2 column and eluting with 10-30% EtOAc/hexanes provided the title compound as a very pale yellow oil as a 3.7:1 mixture of (3S):(3R) diastereomers.

1. customby bubbling argon through the solution for 20 minutes
2. temperatureThe reaction mixture was cooled to rt
3. customand the reaction was quenched by the addition of sat. aqueous NH4Cl (500 mL)
4. customthe layers were separated
5. extractionThe aqueous layer was extracted with EtOAc (2×1 L)
6. washwashed with sat. aq. NaCl solution (1 L)
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated in vacuo

ORD-Eintrag

ord-e625caee65aa4eb2a173a1c6b5845127

Quelldatensatz

uspto-grants-2013_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08569341B2