Reaktion #445412

Reaktionsgleichung

ethanol

ethyl 4,4-bis-(3-tert.-butyl-4-hydroxyphenyl)-valerate

4-hydroxy-2,2,6,6-tetramethylpiperidine

dibutyltin oxide

→

2,2,6,6-tetramethylpiperidin-4-yl 4,4-bis-(3-tert.-butyl-4-hydroxyphenyl)-valerate

Lösungsmittel

xylene

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.DISTILLATIONis distilled off continuously
2. 2
   SonstigeWhen no more ethanol distils off
3. 3
   workup.ADDITIONis efficiently mixed
4. 4
   SonstigeThe organic phase is separated off
5. 5
   Trocknenis dried over magnesium sulfate
6. 6
   Sonstigeis evaporated
7. 7
   SonstigeThe resulting oil is purified by column chromatography

Vorschrift

8.5 g (0.02 mol) of ethyl 4,4-bis-(3-tert.-butyl-4-hydroxyphenyl)-valerate and 3.1 g (0.02 mol) of 4-hydroxy-2,2,6,6-tetramethylpiperidine are dissolved in 200 ml of xylene. 0.1 g of dibutyltin oxide is added, and the mixture is heated at the boil under nitrogen for about 6 hours, during which the resulting ethanol is distilled off continuously. When no more ethanol distils off, the reaction solution is cooled down to room temperature, is admixed with 200 ml of water and is efficiently mixed. The organic phase is separated off, is dried over magnesium sulfate and is evaporated. The resulting oil is purified by column chromatography to give 2,2,6,6-tetramethylpiperidin-4-yl 4,4-bis-(3-tert.-butyl-4-hydroxyphenyl)-valerate in the form of a colourless solid having a melting point of 100°.

Quelle