Methyl 1alpha,3beta-bis(methoxycarbonyloxy)pregna-5,7-diene-20 carboxylate → 1alpha,3beta-Bis(t-butyldimethylsilyloxy)-20-methylpregna-5,7-dien-21-ol
Reaktionsgleichung
[Si:1]([O:8][C@@H:9]1[C@@:31]2([CH3:32])[C:13](=[CH:14][CH:15]=[C:16]3[C@@H:30]2[CH2:29][CH2:28][C@@:27]2([CH3:33])[C@H:17]3[CH2:18][CH2:19][C@@H:20]2[CH:21]([C:23](OC)=[O:24])[CH3:22])[CH2:12][C@@H:11]([O:34][Si:35]([C:38]([CH3:41])([CH3:40])[CH3:39])([CH3:37])[CH3:36])[CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].COC(O[C@@H]1[C@@]2(C)C(=CC=C3[C@@H]2CC[C@@]2(C)[C@H]3CC[C@@H]2C(C(OC)=O)C)C[C@@H](OC(OC)=O)C1)=O>>[Si:1]([O:8][C@@H:9]1[C@@:31]2([CH3:32])[C:13](=[CH:14][CH:15]=[C:16]3[C@@H:30]2[CH2:29][CH2:28][C@@:27]2([CH3:33])[C@H:17]3[CH2:18][CH2:19][C@@H:20]2[CH:21]([CH3:22])[CH2:23][OH:24])[CH2:12][C@@H:11]([O:34][Si:35]([C:38]([CH3:39])([CH3:41])[CH3:40])([CH3:36])[CH3:37])[CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2]Komponenten
3
Versuchsvorschrift
The procedure of Example 11 was repeated except that 85 mg of methyl 1α,3β-bis(t-butyldimethylsilyloxy)pregna-5,7-diene-20-carboxylate was used in lieu of 70 mg of methyl 1α,3β-bis(methoxycarbonyloxy)pregna-5,7-diene-20-carboxylate to give 55 mg of 1α,3β-bis(t-butyldimethylsilyloxy)-20-methylpregna-5,7-diene-21-ol, whose 1H NMR spectrum was identical with that obtained in Example 9.