Reaktion #1960036

Reaktionsgleichung

AlCl3

4-bromo-2-tert-butyl-1-(3-hydroxy-3-methylbutoxy)benzene

→

title compound

Ausbeute 77.2%

6-Bromo-8-tert-butyl-4,4-dimethyl-2,3-dihydrobenzopyran

Ausbeute 77.2%

Lösungsmittel

nitromethane

nitromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe reaction mixture is quenched by slow addition of water
2. 2
   workup.ADDITIONdiluted with hexanes
3. 3
   Waschenwashed with water and brine
4. 4
   ExtraktionThe aqueous layers are extracted with hexanes
5. 5
   Trocknenthe combined organic layers are dried (MgSO4)
6. 6
   Filtrationfiltered
7. 7
   Einengenconcentrated
8. 8
   SonstigeThe residue is purified by flash column chromatography on silica (hexanes)

Vorschrift

To a cold (0° C.) suspension of AlCl3 (1.67 g, 12.51 mmol, 1 equiv) in nitromethane (20 mL) is added a solution of 4-bromo-2-tert-butyl-1-(3-hydroxy-3-methylbutoxy)benzene (3.94 g, 12.51 mmol) in nitromethane (5 mL). The resulting red solution is stirred at 0° C. After 1 h, the reaction mixture is quenched by slow addition of water, diluted with hexanes, and washed with water and brine. The aqueous layers are extracted with hexanes; the combined organic layers are dried (MgSO4), filtered and concentrated. The residue is purified by flash column chromatography on silica (hexanes) to give the title compound (2.87 g, 77%) as a solid which is recrystallized using hexanes to give white crystals.

Quelle