反应 #2200583

反应方程式

water

(S)-(+)-p-toluenesulfinamide

(2S,3S)-2-methyl-3-benzyloxybutyraldehyde

→

(S)-N-[(2R,3S)-2-methyl-3-tetrahydropyranyloxybutylidene]-p-toluenesulfinamide

收率 77.0%

溶剂

dichloromethane

反应条件

后处理

1. 1
   温度The solution was refluxed under argon for 5.5 hours
2. 2
   其他was neutralized at 0° C.
3. 3
   过滤The cloudy solution was filtered on Celite
4. 4
   洗涤the filter cake was washed with dichloromethane (2×25 ml)
5. 5
   其他The phases were separated
6. 6
   萃取the aqueous phase was extracted with dichloromethane
7. 7
   干燥the combined organic portions were dried over Na2SO4 and they
8. 8
   浓缩were concentrated

实验过程

Ti(OEt)4 (1.71 g, 1.57 ml, 7.5 mmol, 5 eq.) was added dropwise, at room temperature, to a mixture of (S)-(+)-p-toluenesulfinamide (233 mg, 1.50 mmol) and (2S,3S)-2-methyl-3-benzyloxybutyraldehyde (6) (280 mg, 1.50 mmol) in dichloromethane (25 ml). The solution was refluxed under argon for 5.5 hours. The reaction was neutralized at 0° C. adding water (25 ml). The cloudy solution was filtered on Celite and the filter cake was washed with dichloromethane (2×25 ml). The phases were separated, the aqueous phase was extracted with dichloromethane and the combined organic portions were dried over Na2SO4 and they were concentrated. Flash chromatography on a silica gel column (heptane/EtOAc=6:1) produced (S)-N-[(2R,3S)-2-methyl-3-tetrahydropyranyloxybutylidene]-p-toluenesulfinamide (7) (375 mg, 77%): IR (CHCl3) 3010, 2976, 2946, 2878, 2854, 1620, 1598, 1494, 1455, 1443, 1380, 1354, 1214 cm−1; 1H NMR (250 MHz, CDCl3) δ 8.31 (d, J=5.8 Hz, 0.5H); 8.23 (d, J=5.3 Hz, 0.5H); 7.55 (m, 2H); 7.29 (m, 2H); 4.79 to 4.70 (m, 0.5H); 4.55 to 4.51 (m, 0.5H); 4.00 to 3.82 (m, 1.5H); 3.77 to 3.70 (m, 0.5H); 3.48 to 3.41 (m, 1H); 2.84 to 2.64 (m, 1H); 2.39 (s, 3H); 1.78 to 1.41 (m, 6H); 1.25 (d, J=6.4 Hz, 1.5H); 1.14 (d, J=5.7 Hz, 3H); 1.14 (d, J=7.1 Hz, 1.5H); 1.09 (d, J=7.0 Hz, 1.5H); 13C NMR (75 MHz, CDCl3) δ 169.2; 168.6; 141.9; 141.8; 141.2; 129.4; 124.4; 124.2; 99.6; 94.6; 76.4; 72.2; 62.3; 61.8; 45.6; 45.2; 30.6; 30.5; 25.2; 25.2; 21.1; 19.4; 19.1; 18.9; 16.3; 13.0; 12.5; MS (CI) m/z 324 [M+H]+. HRMS: calculated for C17H26NO3S (M+H), 324.16333; found, 324.16141.

来源