1alpha,3beta-Bis(methoxycarbonyloxy)pregna-5,7-diene-20-carbaldehyde → 1alpha,3beta-Bis(t-butyldimethylsilyloxy)pregna-5,7-diene-20-carboxylic acid
Reaktionsgleichung
[Si:1]([O:8][C@@H:9]1[C@@:29]2([CH3:30])[C:13](=[CH:14][CH:15]=[C:16]3[C@@H:28]2[CH2:27][CH2:26][C@@:25]2([CH3:31])[C@H:17]3[CH2:18][CH2:19][C@@H:20]2[CH:21]([CH:23]=[O:24])[CH3:22])[CH2:12][C@@H:11]([O:32][Si:33]([C:36]([CH3:39])([CH3:38])[CH3:37])([CH3:35])[CH3:34])[CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].C[O:41]C(O[C@@H]1[C@@]2(C)C(=CC=C3[C@@H]2CC[C@@]2(C)[C@H]3CC[C@@H]2C(C=O)C)C[C@@H](OC(OC)=O)C1)=O>>[Si:1]([O:8][C@@H:9]1[C@@:29]2([CH3:30])[C:13](=[CH:14][CH:15]=[C:16]3[C@@H:28]2[CH2:27][CH2:26][C@@:25]2([CH3:31])[C@H:17]3[CH2:18][CH2:19][C@@H:20]2[CH:21]([C:23]([OH:41])=[O:24])[CH3:22])[CH2:12][C@@H:11]([O:32][Si:33]([C:36]([CH3:38])([CH3:37])[CH3:39])([CH3:34])[CH3:35])[CH2:10]1)([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2]Komponenten
3
Versuchsvorschrift
The procedure of Example 6 was repeated except that 140 mg of 1α,3β-bis(t-butyldimethylsilyloxy)pregna-5,7-diene-20-carbaldehyde was used in lieu of 120 mg of 1α,3β-bis(methoxycarbonyloxy)pregna-5,7-diene-20-carbaldehyde to give 112 mg of 1α,3β-bis(t-butyldimethylsilyloxy)pregna-5,7-diene-20-carboxylic acid.