[C:1]([N:9]1[CH2:14][CH2:13][CH:12]([CH:15]=[O:16])[CH2:11][CH2:10]1)(=[O:8])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH:17]([Mg]Br)=[CH2:18]>>[OH:16][CH:15]([CH:12]1[CH2:13][CH2:14][N:9]([C:1](=[O:8])[C:2]2[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=2)[CH2:10][CH2:11]1)[CH:17]=[CH2:18]To a solution of 500 mg of 1-benzoyl-piperidine-4-carboxaldehyde (step C) in 10 ml TBF at −78° C., was added 2.99 mmol of vinyl magnesium bromide. The solution was warmed to 0° C. and stirred for 1 hour. The reaction was quenched with 15 mL of aq. NH4Cl and extracted with 3×20 ml Et2O and the combined organic layers were dried over MgSO4. The solvent was evaporated under reduced pressure and the residue was purified by flash chromatography with 2:1 hexane:EtOAc followed by 1:1 hexane:EtOAc followed by hexane:EtOAc:MeOH, 50:50:5 to give 411 mg of the title compound. 1H NMR (500 MHz) 1.31 (m, 2H), 1.74 (m, 5H), 2.69 (m, 1H), 2.92 (m, 1H), 4.80 (m, 1H), 3.68 (m, 1H), 5.22 (dd, 2H), 5.84 (m, 1H), 7.43 (m, 5H).
読み込み中…