Reaktion #214439

Reaktionsgleichung

2-(1-carbobenzyloxy-4-hydroxypiperidin-4-yl)-2-methylpropionic acid

diphenylphosphoryl azide

triethylamine

toluene

→

4,4-dimethyl-8-carbobenzyloxy-1-oxa-3,8-diazaspiro[4.5]decan-2-one

Lösungsmittel

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturis heated
2. 2
   Temperaturat reflux for 18 hours
3. 3
   SonstigeEvaporation of solvent
4. 4
   Sonstigegives a residue which
5. 5
   Waschenis washed with 50 ml 1 N hydrochloric acid and 50 ml, 5% sodium bicarbonate
6. 6
   SonstigeEvaporation of the solvent

Vorschrift

A mixture of 2-(1-carbobenzyloxy-4-hydroxypiperidin-4-yl)-2-methylpropionic acid, 1.29 g diphenylphosphoryl azide, 0.47 g triethylamine and 50 ml toluene is heated at reflux for 18 hours. Evaporation of solvent gives a residue which is taken up in 125 ml dichloromethane and is washed with 50 ml 1 N hydrochloric acid and 50 ml, 5% sodium bicarbonate. Evaporation of the solvent followed by trituration with diethyl ether affords 1.86 g 4,4-dimethyl-8-carbobenzyloxy-1-oxa-3,8-diazaspiro[4.5]decan-2-one, mp 208°-209°.

Quelle