Реакция #1050001
ord-da62a93a9668413a96db0b7645487f15
Уравнение реакции
Реагенты
Условия реакции
Обработка
- 1workup.STIRRINGthe mixture was stirred for 3 h at -78° C.
- 2Другоеovernight
- 3Другоеat rt
- 4ДругоеThe reaction mixture was quenched with water (100 mL)
- 5Другоеthe organic layer isolated
- 6ЭкстракцияThe aqueous layer was extracted with two 100-mL portions of ethyl ether
- 7ПромывкаThe combined organic extracts were washed with saturated aqueous NaCI
- 8Другоеdried over Na2 SO4
- 9Концентрированиеconcentrated
Методика
To a solution of 1,3-dithiane (6.77 g, 56.3 mmol) in THF (120 mL) at -78° C. was added dropwise over 10 min n-butyllithium (1.6M in hexane, 50 mmol), and the solution was stirred for 2 h under argon. A solution of 31 (11.1 g, 43.3 mmol) in THF (100 mL) was added, the mixture was stirred for 3 h at -78° C., and overnight at rt. The reaction mixture was quenched with water (100 mL) and the organic layer isolated. The aqueous layer was extracted with two 100-mL portions of ethyl ether. The combined organic extracts were washed with saturated aqueous NaCI, dried over Na2 SO4, and concentrated. Flash chromatography over silica gel (1/9EtOAc:hexane) gave 32 contaminated with 3-dithiane. The latter was removed by sublimation (54° C., 8.0 mm Hg). Recrystallization from Et2O provided pure 32 as a colorless solid (14.8 g, 96%): R.function. =0.40 (1/49 EtOAc:hexane); mp 47°-49° C.; 1H NMR (300 MHz, CDCl3) δ7.66 (d, J=7.8 Hz, 4H), 7.43 (m, 6H), 5.90 (m, 1H), 5.02 (dd, J=17.1, 1.7 Hz, 1H), 4.91 (dd, J=10.2, 1.7 Hz, 1H), 4.26 (s, IH), 2.92 (t, J=11.8 Hz, 2H), 2.71 (m, 2H), 2.19 (m, 2H), 2.07 (m, 2H), 1.37 (m, 2H); 13C NMR (75 MHz, CDCl3) δ141.1, 135.9, 132.4, 130.2, 128.0, 113.2, 32.3, 31.5, 27.5, 25.8, 10.5; IR (film) 3068 (m), 3047 (m), 2897 (s), 2840 (m), 1961 (w), 1890 (w), 1826 (w), 1639 (m), 1490 (w), 1429 (s), 1275 (m), 1112 (s), 1003 (m), 911 (s), 785 (m), 744(s), 703 (s) cm-1 ; MS (FAB) m/e (rel. intensity) 357 (M+, 11), 356 (11), 355 (25), 301 (18), 279 (13), 237 (36), 227 (11), 225 (18), 221 (14), 215 (14), 213 (18), 212 (12), 211 (100), 209 (9), 207 (15); HRMS (FAB) calcd for C20H23S2 Si: 355.1010 (MH+ -2), found: 355.1020. Anal. Calcd for C20 H24S2Si: C, 67.36; H, 6.78. Found: C, 67.08; H, 6.78.