Reaktion #9637

Reaktionsgleichung

bromobenzene

AlCl3

HCl

3-oxabicyclo[3.1.0]hexane-2,4-dione

→

cis-2-(4-bromobenzoyl)cyclopropanecarboxylic acid

Ausbeute 74.6%

Lösungsmittel

DCM

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added
2. 2
   workup.STIRRINGThe solution was stirred for few minutes
3. 3
   Sonstigethe layers were separated
4. 4
   ExtraktionThe aqueous layer was extracted with DCM
5. 5
   Waschenthe combined organic phases were washed with water, brine
6. 6
   Trocknendried over Na2SO4
7. 7
   Einengenconcentrated

Vorschrift

To a cold (0° C.) stirred solution of bromobenzene (9.09 g, 57.89 mmol) and AlCl3 (18.36 g, 137.84 mmol) in dry DCM (150 mL) was added 3-oxabicyclo[3.1.0]hexane-2,4-dione (5.40 g, 48.24 mmol). The reaction mixture was stirred at rt for 3 days. The dark-red solution was then poured into ice-cold water (120 mL), and conc. HCl (10 mL) was added. The solution was stirred for few minutes, and the layers were separated. The aqueous layer was extracted with DCM and the combined organic phases were washed with water, brine, dried over Na2SO4 and concentrated to give cis-2-(4-bromobenzoyl)cyclopropanecarboxylic acid (9.69 g, 65%). LC-MS ret. time 2.50; m/z 270 (MH+); 1H NMR (400 MHz, CD2Cl2) δ 1.54 (m, 1H), 1.85 (m, 1H), 2.37 (m, 1H), 2.88 (m, 1H), 7.65 (m, 2H), 7.90 (m, 2H).

Quelle