Methanol → (2S, 4R)-4-hydroxy-N-(4-nitrobenzyloxycarbonyl)proline methyl ester

反応式

[CH3:1]O.S(Cl)(Cl)=O.[N+:7]([C:10]1[CH:28]=[CH:27][C:13]([CH2:14][O:15][C:16]([N:18]2[CH2:26][C@H:24]([OH:25])[CH2:23][C@H:19]2[C:20]([OH:22])=[O:21])=[O:17])=[CH:12][CH:11]=1)([O-:9])=[O:8]>ClCCl>[OH:25][C@H:24]1[CH2:26][N:18]([C:16]([O:15][CH2:14][C:13]2[CH:27]=[CH:28][C:10]([N+:7]([O-:9])=[O:8])=[CH:11][CH:12]=2)=[O:17])[C@H:19]([C:20]([O:22][CH3:1])=[O:21])[CH2:23]1

参加物

実験手順

To a mixture of methanol (94.5 ml) and dichloromethane (945 ml) under ice cooling are dropwise added thionyl chloride (18.7 ml) and after 5 minutes stirring N-p-nitrobenzyloxycarbonyl-L-hydroxyproline (1: 72.4 g), and the mixture is stirred overnight at room temperature. The reaction mixture is concentrated in vacuum to give crude (2S,4R)-4-hydroxy-2-methoxycarbonyl-1-p-nitrobenzyloxycarbonylpyrrolidine (86.5 g) as pale yellow oil. This product can be used in the next step without further purification. IR ν (CHCl3) cm-1 : 3450, 1742, 1703, 1605. 1HNMR δ (CDCl3) ppm: 1.77(1H, s), 2.05 to 2.45(2H, m), 3.55 to 3.8(2H, m), 3.66, 3.76(3H, 2s), 4.49 to 4.62(2H, m), 5.06 to 5.35(2H, m), 7.43 to 7.56(2H, m), 8.22(2H, d, J=8.2 Hz).