Reaktion #80760

Reaktionsgleichung

N-bromosuccinimide

potassium carbonate

ethyl acetate

2-methoxycarbonylmethyltetrahydroquinoline hydrochloride

→

crude compound

6-Bromo-2-methoxycarbonylmethyltetrahydroquinoline

Lösungsmittel

DMF

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe organic layer was separated
2. 2
   Trocknendried over magnesium sulfate
3. 3
   Einengenconcentrated
4. 4
   workup.DISSOLUTIONThe residue was dissolved in DMF (400 mL)
5. 5
   Extraktionextracted with ether (250 mL)
6. 6
   WaschenThe organic layer was washed with water
7. 7
   Trocknendried over magnesium sulfate
8. 8
   Einengenconcentrated
9. 9
   Sonstigeto give 36 g of the crude title compound (quant) which
10. 10
    Sonstigewas used for the next step without purification

Vorschrift

In a mixture of aqueous solution of potassium carbonate (30 g) and ethyl acetate was dispersed 2-methoxycarbonylmethyltetrahydroquinoline hydrochloride (24.8 g, 0.1 mol). The organic layer was separated, dried over magnesium sulfate, and concentrated. The residue was dissolved in DMF (400 mL) and a solution of N-bromosuccinimide (21.36 g, 0.12 mol)in DMF (400 mL) was added dropwise at 0° C. The mixture was stirred for 5 h at room temperature, poured into water (250 mL), and extracted with ether (250 mL). The organic layer was washed with water, dried over magnesium sulfate, and concentrated to give 36 g of the crude title compound (quant) which was used for the next step without purification. The specimen for characterization was obtained by silica gel column chromatography of the crude compound with 1:1 dichloromethane/hexane to 100% dichloromethane: 1H NMR (270 MHz, CDCl3) δ7.02~7.06 (m, 2H), 6.38 (dd, 1H, J=1.7, 7.3 Hz), 4.53 (br, 1H), 3.75 (s, 3H), 3.72~3.75 (m, 4H), 2.70~2.85 (m, 2H), 2.49~2.53 (m, 1H), 1.89~1.99 (m, 1H), 1.61~1.75 (m, 1H),

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