Reaktion #6491

Reaktionsgleichung

methanol

6-Chloro-1-cyano-3,4-dihydronaphthalene

water

→

title compound

Ausbeute 26.0%

1-Carbomethoxy-6-chloro-3,4-dihydronaphthalene

Ausbeute 26.0%

Lösungsmittel

sulfuric acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe resulting solution was heated at 95°-100° C. for 2.5 h
2. 2
   workup.ADDITION45 mL was added
3. 3
   Einengenconcentrated under reduced pressure
4. 4
   SonstigeThe residue was partitioned between ethyl acetate and water
5. 5
   EinengenThe organic layer was concentrated in vacuo
6. 6
   SonstigeThe residue was purified by chromatography on silica gel
7. 7
   Wascheneluted with 20% ethyl acetate in hexane

Vorschrift

6-Chloro-1-cyano-3,4-dihydronaphthalene (5 g, 263 mmol), lit ref, was dissolved in 77% sulfuric acid in methanol and the resulting solution was heated at 95°-100° C. for 2.5 h. The reaction mixture was allowed to cool to ambient temperature and 45 mL was added, followed by 5 mL of water. The reaction mixture was stirred at ambient temperature for 2 days and then concentrated under reduced pressure. The residue was partitioned between ethyl acetate and water. The organic layer was concentrated in vacuo. The residue was purified by chromatography on silica gel eluted with 20% ethyl acetate in hexane to give 1.53 g (26% yield) of the title compound; MS DCl--NH3M/Z: 240 (M+H)+ ; 1H NMR (CDCl3) δ2.37-2.45 (2H, m), 2.75 (2H, t, J=7.5 Hz), 3.85 (3H, s), 7.15 (1H, d, J=1.5 Hz), 7.15 (1H, d, 9 Hz), 7.2 (1H, d, J=7.5 Hz), 7.77 (1H, d, J=7.5).

Quelle