反应详情

To a warm solution of sodium (181.7 g., 7.9 g-atoms) in ethanol (5 l) was added with stirring a slurry of 2-n-propoxybenzamidine methyl sulfate (1146.7 g., 3.95 moles) in ethanol 1.6 l). After 2-3 minutes diethyl ethoxymethylenemalonate 854 g., 3.95 moles) was added and the mixture stirred and heated under reflux for 2.25 hours. The mixture was cooled and then added to cold water (13 l). The mixture was acidified to pH 5-6 with glacial acetic acid. The solid was collected by filtration, washed with water, and dried to give the title compound (937.8 g.), m.p. 102°-104°. An additional crop of product (101.6 g., m.p. 105°-107°, was obtained from the filtrate and washings. Total yield of product, 1039.4 g. (87%).

1. addition, 3.95 moles) was added
2. temperatureheated
3. temperatureunder reflux for 2.25 hours
4. temperatureThe mixture was cooled
5. filtrationThe solid was collected by filtration
6. washwashed with water
7. customdried