2-methylpropylbenzene

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 45.22 g (0.21 mol) of 4-iodotoluene in 326 g of 75% sulfuric acid are introduced into a 750 ml flask having a reflux condenser, a thermometer, a stirrer and a nitrogen supply. 29.2 g (0.22 mol) of isobutylbenzene are then added, and the heterogeneous mixture is cooled to 1 0° C. 94.7 g (0.41 mol) of ammonium peroxodisulfate are added in portions so that the temperature does not exceed 15° C. The reaction mixture is stirred at room temperature for 5 hours. The reaction mixture is then added over the course of 40 minutes at 5-10° C. to a well stirred suspension of 38.18 g (0.21 mol) of potassium hexafluorophosphate in 600 ml of water and 500 ml of acetic acid ethyl ester. The mixture is maintained at room temperature for 1.5 hours, and the phases are separated. The organic phase is washed with water and 5% sodium hydrogen carbonate, and the solvent is removed in vacuo. 89 g (0.18 mol; 86%) of p-isobutylphenyl-p-tolyl-iodonium hexafluorophosphate are obtained in the form of a brownish resin. The product is purified further by chromatography (dichloromethane:ethanol 95:5 on SiO2) or by recrystallisation from chloroform/hexane. does not exceed 15° C The reaction mixture is then added over the course of 40 minutes at 5-10° C. to a well stirred The mixture is maintained at room temperature for 1.5 hours the phases are separated The organic phase is washed with water and 5% sodium hydrogen carbonate the solvent is removed in vacuo

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 27 g (200 mmol) of isobutylbenzene and 24 mL (215 mmol) of ethyl oxalylchloride underwent Friedel-Crafts acylation reaction in an analogous fashion as described for the synthesis of ethyl 4-phenylbenzoylformate to yield 38 g (81% yield) of ethyl 4-isobutylbenzoylformate as a colorless oil. acylation reaction in an analogous fashion

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

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. the mixture was refluxed for 15 hours were added 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 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)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 17.3 g (125 mmol) of AlCl3 were added to a solution of 6.71 g (50 mmol) of isobutylbenzene in 30 ml of analytical grade methylene chloride, while cooling with ice. 11.9 g (52 mmol) of 2-bromoisobutyryl bromide were then added rapidly, and stirring was continued at 0° C. for 1 hour and at room temperature for 2 hours. The mixture was heated under reflux for a further 15 hours and then worked up analogously to Example A. The crude product was chromatographed on 100 g of silica gel (hexane/methylene chloride 1:1). The yield was 8.42 g (83%). while cooling with ice The mixture was heated under reflux for a further 15 hours The crude product was chromatographed on 100 g of silica gel (hexane/methylene chloride 1:1)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of 1.78 g (10 milliMoles) of N-bromosuccinimide in 20 ml of liquid sulfur dioxide at -30° C. is added 1.57 ml (10.0 mMoles) of isobutylbenzene. The mixture is stirred at -30° to -18° for 65 minutes, then worked up as above. Assay gives only 2% p-bromoisobutylbenzene and 88% recovered starting isobutylbenzene, indicating that the reaction with NBS is very slow at this temperature.