反应详情

A mixture of (3R,4S)-4-(3-cyano-2-methyl-1-isothioureido)-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-carbonitrile (2.12 g) and 50% aqueous dimethylamine solution (10.6 ml) was stirred under reflux for 1.5 hours to form white precipitates. These precipitates were collected by filtration, washed with water, and recrystallized from ethanol to give (3R, 4S)-4 -(2-cyano-3,3-dimethylguanidino)-3,4-dihydro-3-hydroxy-2,2-dimethyl-2H-1-benzopyran-6-carbonitrile (1.03 g).

1. temperatureunder reflux for 1.5 hours
2. customto form white precipitates
3. filtrationThese precipitates were collected by filtration
4. washwashed with water
5. customrecrystallized from ethanol