反応 #8635

反応方程式

1-bromo-2-methylpropane

32

(3-Buten-1-yl)(1,3-dithian-2-yl)diphenylsilane

n-butyllithium

→

26

収率 92.5%

(3-Buten-1-yl) [2-(2-methyl-1-propyl)-1,3-dithian-2-yl]diphenylsilane

収率 92.5%

溶媒

THF

反応条件

後処理

1. 1
   workup.STIRRINGthe mixture was stirred for 2 h at −78° C. and overnight at rt
2. 2
   その他The reaction mixture was quenched with water (10 mL)
3. 3
   その他the excess organic solvent was removed under reduced pressure
4. 4
   抽出The crude mixture was extracted with three 100-mL portions of EtOAc
5. 5
   洗浄The combined organic extracts were washed with saturated aqueous NaCl
6. 6
   乾燥dried over Na2SO4
7. 7
   濃縮concentrated

実験手順

To a solution of 32 (4.68 g, 13.1 mmol) in THF (100 mL) at −78° C. was added dropwise over 10 min n-butyllithium (1.6 M in hexanes, 18.4 mmol). After 3 h of stirring under argon, 1-bromo-2-methylpropane (2.14 mL, 19.7 mmol) was added dropwise over 5 min, and the mixture was stirred for 2 h at −78° C. and overnight at rt. The reaction mixture was quenched with water (10 mL) and the excess organic solvent was removed under reduced pressure. The crude mixture was extracted with three 100-mL portions of EtOAc. The combined organic extracts were washed with saturated aqueous NaCl, dried over Na2SO4, and concentrated. Flash chromatography over silica gel (1/9 EtOAc:hexane) gave pure 26 as a colorless solid (5.0 g, 92%): Rf=0.75 (1/9 EtOAc:hexane); mp 67–69° C.; 1H NMR (300 MHz, CDCl3) δ 7.83 (d, J=6.0 Hz, 4H), 7.41 (m, 6H), 5.88 (m, 1H), 4.97 (dd, J=17.1, 1.7 Hz, 1H), 4.88 (dd, J=10.1, 1.7 Hz, 1H), 3.04 (m, 2H), 2.49 (t. J=4.3 Hz 1H), 2.44 (t, J=4.1 Hz, 1H), 2.08 (d, J=5.1 Hz, 2H), 1.98 (m, 4H), 1.79 (m, 1H), 1.54 (m, 2H), 0.82 (d, J=6.7 Hz, 6H); 13C NMR (75 MHz, CDCl3) δ 141.5, 136.7, 132.9, 129.9, 127.7, 113.0, 45.7, 39.9, 28.3, 27.2, 24.6, 24.3, 24.2, 11.0; IR (film) 3068 (m), 3043 (m), 2951 (s), 2912 (s), 2863 (m), 1432 (s), 1274 (w), 1113 (s), 997 (m), 913 (m), 738 (s), 705 (s) cm−1; MS (EI) m/e (rel. intensity) 289 (M+-123, 3), 237 (8), 183 (72), 175 (100), 159 (32), 143 (17), 119 (16), 105 (35); HRMS (FAB) calcd for C24H32S2Si: 412.1715 (MH+-1), found: 412.1727. Anal. Calcd for C24H32S2Si: C, 69.84; H, 7.82. Found: C, 70.08; H, 8.07.

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