Reaktion #326322

Reaktionsgleichung

5-methylcyclohexane-1,3-dione

hydroxylamine hydrochloride

→

desired compound

Ausbeute 49.3%

6-Methylazepane-2,4-dione

Ausbeute 49.3%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturunder reflux
2. 2
   SonstigeThe solvent was removed in vacuo
3. 3
   workup.DISSOLUTIONthe residue was dissolved in 1 L acetonitrile
4. 4
   workup.ADDITIONTriethylamine was added
5. 5
   workup.ADDITIONfollowed by addition of a solution of 4-toluenesulfonyl chloride in 1.1 L acetonitrile
6. 6
   workup.STIRRINGThe mixture was stirred for 1 h at RT
7. 7
   workup.ADDITION6.7 mL of water was added
8. 8
   workup.STIRRINGthe mixture was stirred for additional 1 h
9. 9
   Temperaturwhile gently warming the mixture to 55° C
10. 10
    SonstigeThe volatiles were removed in vacuo
11. 11
    workup.ADDITION250 mL water was added to the residue
12. 12
    Sonstigethe volatiles were removed in vacuo
13. 13
    ExtraktionThe solids were extracted with acetone
14. 14
    Einengenafter concentration in vacuo the residue
15. 15
    Sonstigewas purified by column chromatography on silica gel with ethyl acetate

Vorschrift

150 g 5-methylcyclohexane-1,3-dione was dissolved in 1.4 L methanol and 82.5 g hydroxylamine hydrochloride was added. The mixture was stirred for 1.5 h under reflux. The solvent was removed in vacuo and the residue was dissolved in 1 L acetonitrile and was cooled to 0° C. Triethylamine was added followed by addition of a solution of 4-toluenesulfonyl chloride in 1.1 L acetonitrile. The mixture was stirred for 1 h at RT, 6.7 mL of water was added and the mixture was stirred for additional 1 h while gently warming the mixture to 55° C. The volatiles were removed in vacuo. 250 mL water was added to the residue and the pH was adjusted to 5 with 5 N aq. NaOH and the volatiles were removed in vacuo. The solids were extracted with acetone and after concentration in vacuo the residue was purified by column chromatography on silica gel with ethyl acetate to yield 82.6 g of the desired compound.

Quelle