Reaktion #76305

Reaktionsgleichung

ethyl 4-[4[4-(hydroxydiphenylmethyl)-1-piperidinyl]-hydroxybutyl]-α,α-dimethylbenzeneacetate

sodium hydroxide

→

4-[4[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-α,α-dimethylbenzeneacetic acid

Lösungsmittel

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture is refluxed for 3½ hours
2. 2
   Einengenconcentrated to a solid after which a minimum amount of methanol
3. 3
   workup.DISSOLUTIONto dissolve the residue
4. 4
   workup.ADDITIONis added
5. 5
   workup.ADDITION10% Aqueous HCl is added until pH 7
6. 6
   Sonstigethe methanol removed by evaporation and water (25 ml)
7. 7
   workup.ADDITIONis added
8. 8
   SonstigeThe resulting precipitate is recrystallized from methanolbutanone

Vorschrift

According to the described procedure of Carr et al., U.S. Pat. No. 4,254,129, to a solution of 0.6 g of ethyl 4-[4[4-(hydroxydiphenylmethyl)-1-piperidinyl]-hydroxybutyl]-α,α-dimethylbenzeneacetate in 20 ml of absolute ethanol is added 10 ml of a 50% solution of sodium hydroxide. The mixture is refluxed for 3½ hours and concentrated to a solid after which a minimum amount of methanol to dissolve the residue is added. 10% Aqueous HCl is added until pH 7 is reached, the methanol removed by evaporation and water (25 ml) is added. The resulting precipitate is recrystallized from methanolbutanone to give 4-[4[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-α,α-dimethylbenzeneacetic acid, M.P. 195°-197° C.

Quelle