Reaktion #700502

Reaktionsgleichung

CO2

3,4-dihydro-1-(4-methylphenyl)-4,4-dimethyl-7-bromonaphthalene

Compound D

3,4-dihydro-1-(4-methylphenyl)-4,4-dimethyl-7-bromonaphthalene

t-butyllithium

→

title compound

5,6-Dihydro-5,5-dimethyl-8-(4-methylphenyl)-2-naphthalenecarboxylic acid

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigewas bubbled through the reaction for 1 hour
2. 2
   Sonstigethe reaction was quenched by the addition of 10% HCl
3. 3
   ExtraktionExtraction with EtOAc
4. 4
   Waschenby washing the combined organic layers with H2O and saturated aqueous NaCl
5. 5
   Trocknendrying over MgSO4
6. 6
   SonstigeRemoval of the solvents under reduced pressure
7. 7
   Waschenwashing of the solid with hexanes

Vorschrift

A solution of 3,4-dihydro-1-(4-methylphenyl)-4,4-dimethyl-7-bromonaphthalene (Compound D) (250.0 mg, 0.764 mmol) in 2.0 ml of THF was cooled to -78° C. and 1.0 ml of t-butyllithium (1.68 mmol, 1.7 M solution in pentane) was added slowly. After stirring for 1 hour at -78° C. gaseous CO2 (generated by evaporation of Dry-Ice, and passed though a drying tube) was bubbled through the reaction for 1 hour. The solution was then allowed to warm to room temperature and the reaction was quenched by the addition of 10% HCl. Extraction with EtOAc was followed by washing the combined organic layers with H2O and saturated aqueous NaCl, and drying over MgSO4. Removal of the solvents under reduced pressure and washing of the solid with hexanes afforded the title compound as a colorless solid. 1H NMR (CDCl3): δ 7.94 (1H, dd, J=1.8, 8.1 Hz), 7.76 (1H, d, J=1.8 Hz), 7.45 (1H, d, J=8.1 Hz), 7.24 (4H, m), 6.01 (1H, t, J=4.7 Hz), 2.40 (3H, s), 2.36 (2H, d, J=4.7 Hz), 1.35 (6H, s).

Quelle