C([O:3][C:4]([CH:6]=[C:7]1[CH2:12][CH2:11][N:10]([C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[CH2:9][CH2:8]1)=O)C.[H-].C([Al+]CC(C)C)C(C)C.C1(C)C=CC=CC=1.CO.[H-].C([Al+]CC(C)C)C(C)C>C1(C)C=CC=CC=1.O>[OH:3][CH2:4][CH:6]=[C:7]1[CH2:8][CH2:9][N:10]([C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[CH2:11][CH2:12]1
To a solution of 19.901 g (73.888 mM) of tert-butyl 4-(ethoxycarbonylmethylene)piperidine-1-carboxylate in 100 ml of toluene was added 123 ml (185 mM) of 1.5 M diisobutylaluminum hydride-toluene at −78° C. and the mixture was stirred at −78° C. for 1 hour. Then, methanol was added at −78° C. and the mixture was stirred for 0.5 hour to decompose the excess diisobutylaluminum hydride. Then, water was added under ice-cooling and the mixture was stirred for 2 hours. The resulting precipitate was filtered off with the aid of celite and the celite was washed with ethyl acetate. The filtrate and washes were pooled and the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=3/1 to 1/1) to provide the title compound.
Loading…
