HCID 49765219, compound → tert-Butyl [(3S,5S)-5-methylpiperidin-3-yl]carbamate

Participants

Reaction Conditions

Reaction Steps

A 40 L pressure vessel is charged with 0.6 Kg 50% wet, solid palladium on carbon (E101, 10 wt. %) under flow of nitrogen. A solution of 3.2 Kg intermediate (7) in 13.7 Kg of absolute ethanol is then charged to the reactor under nitrogen. The reactor is purged with nitrogen and is then pressurized with hydrogen at 45 psi. The reaction is then heated to 45° C. while maintaining a hydrogen pressure of 45 psi. The reaction is monitored by TLC or LC until complete. The reaction is cooled to ambient temperature, vented, and purged with nitrogen. The reactor contents are filtered through a bed of Celite and the solids are washed with 2.8 Kg of absolute ethanol. The filtrate is concentrated by rotary evaporation under vacuum until a waxy solid is obtained to afford intermediate (8): TLC Rf (Silica F254, 70:30 v/v ethyl acetate-hexanes, KMnO4 stain)=0.12; 1H NMR (300 MHz, CDCl3) δ5.31 (br s, 1H), 3.80-3.68 (m, 1H), 2.92 (d, J=11.4 Hz,1H), 2.77 (AB quart, JAB=12.0 Hz, Δv=50.2 Hz, 2H), 2.19 (t, J=10.7 Hz, 1H), 1.82-1.68 (m, 2H), 1.54 (br s, 1H), 1.43 (s, 9H), 1.25-1.15 (m, 1H), 0.83 (d, J=6.6 Hz, 3H); 13C NMR (75 MHz, CDCl3) δ 155.3, 78.9, 54.3, 50.8, 45.3, 37.9, 28.4, 27.1, 19.2; MS (ESI+) m/z 215 (M+H), 429 (2M+H).

Provenance & Evidence