Sodium borohydride → t-Butyldimethylsilyl-3-(1'-hydroxy-2'-phenylethyl)-4-tritylthio-2-azetidinone
反応式
[Si:1]([N:8]1[C@@H:11]([S:12][C:13]([C:26]2[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=2)([C:20]2[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=2)[C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=2)[C@H:10]([C:32](=[O:40])[CH2:33][C:34]2[CH:39]=[CH:38][CH:37]=[CH:36][CH:35]=2)[C:9]1=[O:41])([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].[BH4-].[Na+]>C1COCC1>[Si:1]([N:8]1[CH:11]([S:12][C:13]([C:20]2[CH:21]=[CH:22][CH:23]=[CH:24][CH:25]=2)([C:14]2[CH:15]=[CH:16][CH:17]=[CH:18][CH:19]=2)[C:26]2[CH:31]=[CH:30][CH:29]=[CH:28][CH:27]=2)[CH:10]([CH:32]([OH:40])[CH2:33][C:34]2[CH:39]=[CH:38][CH:37]=[CH:36][CH:35]=2)[C:9]1=[O:41])([C:4]([CH3:6])([CH3:7])[CH3:5])([CH3:3])[CH3:2]参加物
4
実験手順
trans 1-(t-butyldimethylsilyl)-3-phenylacetyl-4-tritylthio-2-azetidinone (28.8 g, 50 mmol) and NaBH4 (0.5 g, 0.25 mole) in THF (200 ml) were stirred at room temperature for 18 h. The mixture was poured onto ice-1N HCl and extracted with CH2Cl2. The CH2Cl2 solution was washed with brine and dried (Na2SO4). It was evaporated to give an amorphous solid (27.7 g). A portion of the solid (23.0 g) was chromatographed on SiO2 and eluted with hexane:ether to give off-white solid (14.4 g) which was found to be a mixture of (1'R,3S,4R and 1'S,3R,4S) and (1'S,3S,4R and 1'R,3R,4S) isomers in the ratio of 1:1 (60%). 1Hmr (CDCl3) δ: 7-7.7 (20H, m), 4.37 (1/2H, d), 4.18 (1/2H, d), 3.3-3.8 (H, m), 3.45 (1/2H, dd), 3.1 (1/2H, dd), 2.7 (2H, m), 0.87 (9H, d) and 0.25 ppm (6H, s).