Reaktion #61285

Reaktionsgleichung

5-Ethyl-6-(4-hydroxy-3-methyl-but-2-enyl)-4-methyl-7-(2-trimethylsilanyl-ethoxy)-3H-isobenzofuran-1-one

triphenylphosphine

Carbon tetrabromide

→

desired product

Ausbeute 87.0%

6-(4-Bromo-3-methyl-but-2-enyl)-5-ethyl-4-methyl-7-(2-trimethylsilanyl-ethoxy)-3H-isobenzofuran-1-one

Ausbeute 87.0%

Lösungsmittel

DCM

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe solution was stirred at room temperature
2. 2
   Filtrationthe reaction was filtered
3. 3
   Sonstigethe solvent was removed in vacuo
4. 4
   SonstigeThe crude material was purified by silica gel chromatography

Vorschrift

5-Ethyl-6-(4-hydroxy-3-methyl-but-2-enyl)-4-methyl-7-(2-trimethylsilanyl-ethoxy)-3H-isobenzofuran-1-one (57.2 mg, 0.152 mmol) was dissolved in DCM (3.5 mL). Polymer-bound triphenylphosphine (3 mmol/g, 152.1 mg) was added and the mixture was mechanically stirred at room temperature. Carbon tetrabromide (151.3 mg, 0.456 mmol) was added and the solution was stirred at room temperature. After 2 hours, the reaction was filtered and the solvent was removed in vacuo. The crude material was purified by silica gel chromatography to provide 58.0 mg (87%) of the desired product. 1H NMR (300 MHz, CDCl3): δ=0.04 (s, 9H), 1.15 (t, J=7.8 Hz, 3H), 1.25 (m, 2H), 1.95 (s, 3H), 2.20 (s, 3H), 2.70 (q, J=7.8 Hz, 2H), 3.52 (d, J=6.3 Hz, 2H), 3.94 (s, 2H), 4.28 (m, 2H), 5.14 (s, 2H), 5.50 (m, 1H) ppm.

Quelle