Phenyl isocyanate → 7a-(3-ethyl-5-isoxazolyl)-hexahydro-1H-pyrrolizine

반응식

[N+:1]([CH2:4][CH2:5][CH3:6])([O-:3])=O.C1(N=C=O)C=CC=CC=1.[C:16]([C:18]12[CH2:25][CH2:24][CH2:23][N:22]1[CH2:21][CH2:20][CH2:19]2)#[CH:17]>C1C=CC=CC=1>[CH2:5]([C:4]1[CH:17]=[C:16]([C:18]23[CH2:25][CH2:24][CH2:23][N:22]2[CH2:21][CH2:20][CH2:19]3)[O:3][N:1]=1)[CH3:6]

참가 물질

실험 절차

Nitropropane (0.475 mL, 5.29 mmol) and phenylisocyanate (1.0 mL, 9.5 mmol) were dissolved in benzene (10 mL) and added to a flask containing 7a-ethynyl-hexahydro-1H-pyrrolizine (358 mg, 2.65 mmol, from step 13a). The solution was stirred at ambient temperature for 1 hour and at reflux for 5 hours. The mixture was cooled, filtered, concentrated and diluted with EtOAc. The solution was extracted with 6N HCl. The aqueous phase was made basic with 15% NaOH and extracted with methylene chloride. The organic extracts were combined, dried (MgSO4) and concentrated. The residue was residue was chromatographed (silica gel; CHCl3 /MeOH, 98:2) to afford an amber oil (274 mg, 50%). 1H NMR (CDCl3, 300 MHz) δ1.25 (t, J=7.5 Hz, 3H), 1.75-1.92 (m, 6H), 2.15-2.25 (m, 2H), 2.60-2.69 (m, 4H), 3.13-3.20 (m, 2H), 5.98 (s, 1H); MS (CI/NH3) m/z: 207 (M+H)+.