Reaktion #1462220

Reaktionsgleichung

2,6-lutidine

(2R)-4-benzyl-1-[3,5-bis(trifluoromethyl)benzoyl]-2-(4-hydroxy-3-methoxybenzyl)piperazine

Trifluoromethane sulfonic acid anhydride

hydrochloric acid

→

trifluoromethanesulfonic acid 4-[[(2R)-1-[3,5-bis(trifluoro-methyl)benzoyl]-4-benzylpiperazin-2-yl]methyl]-2-methoxyphenyl ester

Lösungsmittel

water

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe organic layer was separated
2. 2
   Trocknendried over magnesium sulfate
3. 3
   Sonstigeevaporated under reduced pressure
4. 4
   SonstigeThe residue was purified by column chromatography on silica gel using
5. 5
   workup.ADDITIONa mixture of toluene and ethyl acetate (100:1–5:1)

Vorschrift

Trifluoromethane sulfonic acid anhydride (5.25 ml) was added dropwise over 30 minutes to an ice-cooled solution of (2R)-4-benzyl-1-[3,5-bis(trifluoromethyl)benzoyl]-2-(4-hydroxy-3-methoxybenzyl)piperazine (14.3 g) and 4-(dimethylamino)pyridine (0.47 g) and 2,6-lutidine (3.6 ml) in dichloromethane (150 ml) below 10° C. After being stirred at the same temperature for 2 hours, the reaction mixture was poured into water. The pH of the whole mixture was adjusted to 7 with diluted hydrochloric acid and the organic layer was separated, dried over magnesium sulfate and evaporated under reduced pressure. The residue was purified by column chromatography on silica gel using a mixture of toluene and ethyl acetate (100:1–5:1) to give the objective trifluoromethanesulfonic acid 4-[[(2R)-1-[3,5-bis(trifluoro-methyl)benzoyl]-4-benzylpiperazin-2-yl]methyl]-2-methoxyphenyl ester as an oil.

Quelle