반응 단계
To a solution of 1,3-dithiane (11.1 g, 91.9 mmol) in THF (150 mL) at −78° C. was added dropwise over 10 min n-butyllithium (1.6 Min hexane, 76.6 mmol), and the solution was stirred for 2 h under argon. A solution of 42 (11.9 g, 61.3 mmol) in THF (120 mL) was added dropwise over 30 min, and the mixture was stirred for 3 h at −78° C. and overnight at rt. The reaction mixture was quenched with water (100 mL) and extracted thrice with 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 43 contaminated with 1,3-dithiane. The latter was removed by sublimation (54° C., 8.0 mm Hg) to provide pure 43 as a yellow oil (9.0 g, 50% for three steps from dichlorosilane):Rf=0.55 (1/9 EtOAc:hexane); 1H NMR (300 MHz, CDCl3) δ 7.63-7.61 (m, 2H), 7.42-7.38 (m, 3H), 5.97-5.84 (m, 1H), 5.06-4.90 (m, 2H), 3.95 (s, 1H), 2.93-2.83 (m, 2H), 2.72-2.67 (m, 2H), 2.21-1.97 (m, 4H), 1.18-1.09 (m, 2H), 0.49 (s, 3H); 13C NMR (75 MHz, CDCl3) δ 141.0, 134.5, 134.1, 129.9, 127.9, 113.2, 32.9, 31.1, 31.0, 27.2, 25.8, 10.8, 7.0; MS (FAB) m/e (rel. intentsity) 293 (MH+, 23), 239 (21), 175 (20), 159 (9), 149 (58), 121 (100), 119 (37), 115 (23), 105 (34), 97 (28), 92 (22); HRMS (FAB) calcd for C15H22S2Si: 293.0854, found: 293.0861. Anal. Calcd for C15H22S2Si: C, 61.16; H, 7.53. Found C, 61.31; H, 7.74.
