Reaction #362814

Reaction equation

aluminum trichloride

isobutyl benzene

HCl

2-bromoisobutyryl bromide

→

1

Yield 83.0%

(±)-2-Methyl-5-isobutyl-1-indanone

Yield 83.0%

Solvents

methylene chloride

Conditions

Workup

1. 1
   Temperaturethe mixture was refluxed for 15 hours
2. 2
   workup.ADDITIONwere added
3. 3
   Extractionthe mixture was extracted 3 times with 50 ml of diethyl ether in each case
4. 4
   WashThe combined organic phases were washed with 50 ml each of saturated aqueous NaHCO3 solution and NaCl solution
5. 5
   Dryingdried (MgSO4)
6. 6
   OtherAfter removal of the solvent
7. 7
   Otheron a rotary evaporator
8. 8
   Otherthe crude product was chromatographed on 100 g of silica gel (hexane/methylene chloride 1:1)

Procedure

17.3 g (125 mmol) of aluminum trichloride were added with ice cooling to a solution of 6.7 g (50 mmol) of isobutyl benzene in 30 ml of methylene chloride. 11.9 g (52 mmol) of 2-bromoisobutyryl bromide were subsequently added rapidly, and the mixture was refluxed for 15 hours. The reaction mixture was poured into 100 ml of ice water, 25 ml of conc. aqueous HCl were added, and the mixture was extracted 3 times with 50 ml of diethyl ether in each case. The combined organic phases were washed with 50 ml each of saturated aqueous NaHCO3 solution and NaCl solution and dried (MgSO4). After removal of the solvent on a rotary evaporator, the crude product was chromatographed on 100 g of silica gel (hexane/methylene chloride 1:1), giving 8.4 g (83%) of 1 as a colorless oil.

Source