Reaktion #4193

Reaktionsgleichung

1-(2-nitrophenyl)-1,2,3,4-tetrahydroquinoline

N-bromosuccinimide

sodium hydroxide

→

product

Ausbeute 82.7%

6-Bromo-1-(2-nitrophenyl)-1,2,3,4-tetrahydroquinoline

Ausbeute 82.7%

Lösungsmittel

dimethylformamide

dimethylformamide

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe reaction temperature below 0° C. (1.5 hours)
2. 2
   workup.ADDITIONHalf-an hour after the addition
3. 3
   SonstigeThe product separated as an oil
4. 4
   SonstigeThe quench fluids were decanted
5. 5
   Waschenthe oil was rinsed several times with water
6. 6
   workup.DISSOLUTIONThe oil was dissolved in dichloromethane (1.5 l)
7. 7
   ExtraktionThe organic solution was extracted once with 2N-sodium hydroxide solution, thrice with water
8. 8
   Trocknendried over sodium sulfate
9. 9
   Einengenconcentrated
10. 10
    workup.DISSOLUTIONThe residue was dissolved in 1:1 hexane
11. 11
    Sonstigetoluene (250 ml) and the solution was absorbed on a chromatography column
12. 12
    workup.ADDITIONcontaining 2 kg of silica gel
13. 13
    WaschenElution with this solvent mixture

Vorschrift

A stirred solution, under nitrogen, of 1-(2-nitrophenyl)-1,2,3,4-tetrahydroquinoline (76.3 g, 0.30 mole) in dimethylformamide (1000 ml) was cooled to -10° C. A solution of of N-bromosuccinimide (58.7 g, 0.33 mole) in dimethylformamide (250 ml) was added dropwise at such a rate as to keep the reaction temperature below 0° C. (1.5 hours). Half-an hour after the addition was completed, the reaction mixture was poured into 7 liters of 2N-sodium hydroxide solution/ice, with stirring. The product separated as an oil. The quench fluids were decanted and the oil was rinsed several times with water. The oil was dissolved in dichloromethane (1.5 l). The organic solution was extracted once with 2N-sodium hydroxide solution, thrice with water, dried over sodium sulfate and concentrated. The residue was dissolved in 1:1 hexane:toluene (250 ml) and the solution was absorbed on a chromatography column containing 2 kg of silica gel packed in 1:1 hexane:toluene. Elution with this solvent mixture provided 82.7 g (82%) of product, as an oil. For analysis, a sample was Kugelrohr distilled at a vessel temperature of 166°-168° C. (0.2 mm Hg).

Quelle