Reaktion #566630

Reaktionsgleichung

1-chloroethyl chloroformate

1-chloroethyl chloroformate

7-methoxy-N-methyl-4-phenylspiro[2H-1-benzopyran-2,4′-piperidine]

potassium carbonate

→

title compound

Ausbeute 109.2%

7-Methoxy-4-phenylspiro[2H-1-benzopyran-2,4′-piperidine]

Ausbeute 109.2%

Lösungsmittel

1,2-dichloropropane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe resulting suspension was cooled in an ice-bath
2. 2
   TemperaturThe reaction mixture was heated
3. 3
   Temperaturto reflux overnight
4. 4
   Temperaturwas heated
5. 5
   Temperaturto reflux for a further 24 h
6. 6
   TemperaturUpon cooling
7. 7
   Filtrationthe reaction mixture was filtered through cotton wool which
8. 8
   Waschenwas subsequently washed with dichloromethane (50 cm3)
9. 9
   Sonstigethe volatiles were removed in vacuo
10. 10
    workup.ADDITIONThe resulting intermediate was treated with methyl alcohol (200 cm3)
11. 11
    Temperaturthe mixture was heated
12. 12
    Temperaturto reflux overnight
13. 13
    TemperaturUpon cooling
14. 14
    Sonstigethe volatiles were removed in vacuo before the resulting solid
15. 15
    workup.DISSOLUTIONwas dissolved in a mixture of dichloromethane (150 cm3) and aqueous sodium carbonate solution (5%, 30 cm3)
16. 16
    SonstigeThe organic layer was separated
17. 17
    Waschenwashed with water (2×50 cm3)
18. 18
    Trocknendried over sodium sulfate
19. 19
    Sonstigethe solvent was removed in vacuo

Vorschrift

To a stirred solution of 7-methoxy-N-methyl-4-phenylspiro[2H-1-benzopyran-2,4′-piperidine] (3.76 g, 11.71 mmol) in anhydrous 1,2-dichloropropane (150 cm3) was added potassium carbonate (4.04 g, 29.23 mmol) and the resulting suspension was cooled in an ice-bath before being treated drop-wise with 1-chloroethyl chloroformate (1.58 cm3, 14.64 mmol). The reaction mixture was heated to reflux overnight and a further portion of 1-chloroethyl chloroformate (0.8 cm3, 7.4 mmol) was added before it was heated to reflux for a further 24 h. Upon cooling, the reaction mixture was filtered through cotton wool which was subsequently washed with dichloromethane (50 cm3) and the volatiles were removed in vacuo. The resulting intermediate was treated with methyl alcohol (200 cm3) and the mixture was heated to reflux overnight. Upon cooling, the volatiles were removed in vacuo before the resulting solid was dissolved in a mixture of dichloromethane (150 cm3) and aqueous sodium carbonate solution (5%, 30 cm3). The organic layer was separated, washed with water (2×50 cm3), dried over sodium sulfate and the solvent was removed in vacuo to afford the title compound as a gum (3.93 g).

Quelle