反应详情

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°.

1. temperaturethe mixture cooled to 0°
2. washwashed with ether
3. 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. customThe solid which was obtained
5. customwas dried
6. customrecrystallised from ethyl acetate/petroleum ether