Reaktion #10262

Reaktionsgleichung

(2R)-1-[3,5-bis(trifluoromethyl)benzoyl]-2-(1H-indol-3-ylmethyl)-4-(2-propanon-1-yl)piperazine

O-[2-(dimethylamino)ethyl]hydroxylamine dihydrochloride

sodium acetate

→

1-{(2R)-1-[3,5-bis(trifluoromethyl)benzoyl]-2-(1H-indol-3-ylmethyl)-piperazin-4-yl}-2-propanone O-[2-(dimethylamino)-ethyl]oxime

Ausbeute 104.0%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas heated
2. 2
   Temperaturunder reflux for 2 h
3. 3
   SonstigeThe solvent was removed in vacuo
4. 4
   workup.ADDITIONthe residue was treated with dichloromethane and NAOH (aq, 2N)
5. 5
   SonstigeThe layers were separated
6. 6
   Sonstigethe organic layer was dried
7. 7
   Einengenconcentrated in vacuo
8. 8
   SonstigeThe residue was purified by flash chromatography (SiO2, CH2Cl2/MeOH/NH4OH 92/7.5/0.5)

Vorschrift

A mixture of (2R)-1-[3,5-bis(trifluoromethyl)benzoyl]-2-(1H-indol-3-ylmethyl)-4-(2-propanon-1-yl)piperazine (255 mg), O-[2-(dimethylamino)ethyl]hydroxylamine dihydrochloride (89 mg), sodium acetate (catalytically), and methanol (10 mL) was heated under reflux for 2 h. The solvent was removed in vacuo, and the residue was treated with dichloromethane and NAOH (aq, 2N). The layers were separated, the organic layer was dried and concentrated in vacuo. The residue was purified by flash chromatography (SiO2, CH2Cl2/MeOH/NH4OH 92/7.5/0.5) to afford 1-{(2R)-1-[3,5-bis(trifluoromethyl)benzoyl]-2-(1H-indol-3-ylmethyl)-piperazin-4-yl}-2-propanone O-[2-(dimethylamino)-ethyl]oxime 0.31 g (>95%) as an E/Z mixture. Rf 0.26 (CH2Cl2/MeOH/NH4OH 92/7.5/0.5).

Quelle