Réaction #71007

Équation de réaction

1-(2,2,4-trimethyl-cyclohex-3-enyl)-ethanone

pyridine

methoxyamine hydrochloride

→

1-(2,2,4-trimethyl-cyclohex-3-enyl)-ethanone O-methyl-oxime

Rendement 92.4%

Solvants

methanol

Conditions de réaction

Traitement

1. 1
   AutreMethanol was removed under reduced pressure
2. 2
   workup.ADDITIONthe residue poured in water (600 ml)
3. 3
   workup.ADDITION1N hydrochloric acid was added (100 ml)
4. 4
   ExtractionThe solution was extracted with dichloromethane (3×300 ml)
5. 5
   LavageCombined organic layers were washed with brine (500 ml)
6. 6
   Séchagedried over sodium sulfate
7. 7
   AutreThe solvent was removed in vacuo

Mode opératoire

To a stirred solution of 1-(2,2,4-trimethyl-cyclohex-3-enyl)-ethanone (162 g; 0.97 mol), prepared as described in example P4, in methanol (500 ml) was added pyridine (160 ml; 1.95 mol) followed by a portionwise addition of methoxyamine hydrochloride (142 g; 1.70 mol). The reaction mixture was stirred at 24° C. for 16 hours under nitrogen atmosphere. Methanol was removed under reduced pressure, the residue poured in water (600 ml) and 1N hydrochloric acid was added (100 ml). The solution was extracted with dichloromethane (3×300 ml). Combined organic layers were washed with brine (500 ml) and dried over sodium sulfate. The solvent was removed in vacuo to afford 175 g (92% of theory) of 1-(2,2,4-trimethyl-cyclohex-3-enyl)-ethanone O-methyl-oxime as a clear red oil.

Source