Cis-5-(N-methylcarbamyl)-1-benzylpyrrolidine-2-carboxylic acid → 8-Benzyl-3-methyl-3,8-diazabicyclo[3.2.1]octane-2,4-dione
反応式
[CH3:1][NH:2][C:3]([C@H:5]1[N:9]([CH2:10][C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=2)[C@@H:8]([C:17]([OH:19])=O)[CH2:7][CH2:6]1)=[O:4]>C(OC(=O)C)(=O)C>[CH2:10]([N:9]1[CH:5]2[CH2:6][CH2:7][CH:8]1[C:17](=[O:19])[N:2]([CH3:1])[C:3]2=[O:4])[C:11]1[CH:12]=[CH:13][CH:14]=[CH:15][CH:16]=1参加物
3
実験手順
Cis-5-(N-methylcarbamyl)-1-benzylpyrrolidine-2-carboxylic acid (32.3 g, 0.123 mole) and acetic anhydride (160 ml) were heated together at 100°C for 45 minutes after all of the solid had dissolved. Removal of solvent in vacuo left a red-brown oil that was dissolved in a minimum amount of benzene. After removal of 2.0 g of unreacted cis-5-(N-methylcarbamyl)-1-benzylpyrrolidine-2-carboxylic acid by filtration, the solution of desired product was chromatographed on 900 g alumina with benzene elution to give 13.2 g (44%) of pure, oily 8-benzyl-3-methyl-3,8-diazabicyclo[3.2.1]octane-2,4-dione. Treatment of a sample with excess ethanolic hydrogen chloride in diethyl ether solution produced a hydrochloride salt, melting point 140°-170°C. A sample of the free base, melting point 73°-75°C, was subsequently obtained by slow crystallization from benzene.