反应详情

To 50 mL absolute ethanol was added (E)-3-(dimethylamino)-1-(pyridin-4-yl)prop-2-en-1-one (20 g; Example 1, Step 1). When all solids dissolved, 6.33 mL hydrazine monohydrate was added dropwise with stirring. After 30 minutes an additional 1.1 mL hydrazine hydrate was added. After 2 hours the reaction was treated with water and the yellow solution was concentrated under vacuum until a slurry formed. The resulting solid product was collected by vacuum filtration, washed with water, and dried under high vacuum overnight to yield 15.27 g (93% yield) of product as off-white crystals. 1H NMR (CDCl3) was consistent with a tautomeric mixture of the desired structure. LC/MS showed one peak with a M+1 molecular ion of m/z 146.4 by positive ESI.

1. dissolutionWhen all solids dissolved
2. concentrationthe yellow solution was concentrated under vacuum until a slurry
3. customformed
4. filtrationThe resulting solid product was collected by vacuum filtration
5. washwashed with water
6. customdried under high vacuum overnight