Reaktion #48047

Reaktionsgleichung

N-bromosuccinimide

dibenzoyl peroxide

4-(heptafluoroisopropyl)-toluene

2-nitropropane

sodium

→

4-(1,2,2,2-tetrafluoro-1-trifluoromethyl-ethyl)-benzaldehyde

Ausbeute 30.0%

Lösungsmittel

tetrachloromethane

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Filtrationfiltered
2. 2
   Sonstigethe solvent was evaporated
3. 3
   workup.DISSOLUTIONThe remaining residue was dissolved in 15 ml ethanol
4. 4
   workup.ADDITIONwas added to a suspension that
5. 5
   FiltrationThen it was filtered
6. 6
   Sonstigethe solvent was removed
7. 7
   workup.DISSOLUTIONthe remaining residue was dissolved in EtOAc
8. 8
   Waschenwashed with 1 N sodium hydroxide solution, 1 N HCl solution, saturated NaHCO3 solution and with brine
9. 9
   TrocknenThe EtOAc layer was then dried with magnesium sulfate
10. 10
    Filtrationfiltered
11. 11
    Einengenconcentrated
12. 12
    SonstigePurification of the residue (silica gel; c-hexane/EtOAc 10:1)

Vorschrift

A solution of 3.5 g of 4-(heptafluoroisopropyl)-toluene (13.4 mmol) in 100 ml tetrachloromethane was heated to reflux. Then 2.63 g of N-bromosuccinimide (14.8 mmol) and 326 mg of dibenzoyl peroxide (1.34 mmol) were added in small portions. After 5 h the mixture was cooled to 0° C., filtered and the solvent was evaporated. The remaining residue was dissolved in 15 ml ethanol and was added to a suspension that had been prepared by addition of 2-nitropropane (1.4 ml, 15.5 mmol) to a solution of 340 mg sodium (14.8 mmol) in ethanol. This mixture was stirred for 3 days. Then it was filtered, the solvent was removed and the remaining residue was dissolved in EtOAc and washed with 1 N sodium hydroxide solution, 1 N HCl solution, saturated NaHCO3 solution and with brine. The EtOAc layer was then dried with magnesium sulfate, filtered and concentrated. Purification of the residue (silica gel; c-hexane/EtOAc 10:1) gave 1.1 g (30%) of 4-(1,2,2,2-tetrafluoro-1-trifluoromethyl-ethyl)-benzaldehyde as a light yellow oil. 1H-NMR (CDCl3, 300 MHz: δ 7.82 (d, J=8 Hz, 2H), 8.03 (d, J=8 Hz, 2H), 10.11 (s, 1H).

Quelle