Reaktion #54264

Reaktionsgleichung

sodium hydroxide

sodium hydroxide

1-amino-2-methylpropanephosphonous acid

benzyl chloroformate

→

1-carbobenzyloxyamino-2-methylpropanephosphonous acid

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe mixture cooled to 0°
2. 2
   Waschenwashed with ether
3. 3
   workup.ADDITIONThe aqueous portion was added slowly to a mixture of 120 parts of water and 80 parts of concentrated hydrochloric acid and 400 parts of ice
4. 4
   SonstigeThe solid which was obtained
5. 5
   Sonstigewas dried
6. 6
   Sonstigerecrystallised from ethyl acetate/petroleum ether

Vorschrift

27.5 parts of DL-1-amino-2-methylpropanephosphonous acid in 100 parts of water was stirred until solution occurred. The pH of the solution was adjusted to 9.5 with 4N sodium hydroxide and the mixture cooled to 0°. 34 Parts of benzyl chloroformate was added over 1 hour and the mixture stirred for 6 hours maintaining at pH 9.0-9.5 by periodic addition of 4N sodium hydroxide. The mixture was allowed to warm up to room temperature and then washed with ether. The aqueous portion was added slowly to a mixture of 120 parts of water and 80 parts of concentrated hydrochloric acid and 400 parts of ice. The solid which was obtained was dried and recrystallised from ethyl acetate/petroleum ether to give DL-1-carbobenzyloxyamino-2-methylpropanephosphonous acid, melting point 108°-111°.

Quelle