Hydrochloric Acid → 3,5-Dibromo-1-trimethylsilylbenzene

温度

-55 °C

42.4 g of Tribromobenzene (134.6 mmol) was dissolved in 600 mL Et2O. The solution was chilled to −55° C., at which temperature starting material precipitated. 54 mL of n-BuLi (2.5 M in hexanes, 135 mmol) were added within 20 minutes. After stirring for 35 minutes at −52° C., 20 ml TMSCl (158 mmol) and 20 mL Et2O were added within 7 minutes. The suspension turned into a solution at −42° C., and a fine precipitate appeared at −30° C. The suspension was stirred overnight at room temperature. 100 mL 2M HCl were used to hydrolyze the mixture. After stirring for 30 minutes, the Et2O—phase was dried with MgSO4, filtered, and solvent evaporated until compound crystallized out of solution. The flask was stored overnight at +4° C. The crystalline compound was filtered, washed with a small amount cold pentane, and dried under vacuo. A second fraction of crystalline compound was obtained from the filtrate. Yield: 31.9 g (103.5 mmol, 77%). 1H-NMR (CHCl3=7.24 ppm): δ 7.62 (t, 1H), 7.49 (d, 2H), 0.25 (s, 3×3H).

1. customprecipitated
2. customturned into a solution at −42° C.
3. customappeared at −30° C
4. stirringThe suspension was stirred overnight at room temperature
5. stirringAfter stirring for 30 minutes
6. dry with materialthe Et2O—phase was dried with MgSO4
7. filtrationfiltered
8. customsolvent evaporated until compound
9. customcrystallized out of solution
10. waitThe flask was stored overnight at +4° C
11. filtrationThe crystalline compound was filtered
12. washwashed with a small amount cold pentane
13. customdried under vacuo
14. customA second fraction of crystalline compound was obtained from the filtrate

ORDレコード

ord-e1bc8de25a1748c0a9ad56a4846e6361

出典データセット

uspto-grants-2002_04

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US06376409B1