反应详情

温度

90 °C

4.65 g of diethyl 2-methyl-3-oxobutanedioate (23.0 mmol, 1.00 eq.) were dissolved in 100 mL of dry dioxane under argon atmosphere. 2.1 mL of glacial acetic acid and 6.32 g of (4-ethoxy-2,6-difluorobenzyl)hydrazine dihydrochloride (23.00 mmol, 1.00 eq.) were added. The mixture was stirred for 16 hours at 90° C. bath temperature. The reaction mixture was evaporated in vacuo. The residue was stirred with ethyl acetate. The resulting suspension was filtered off and washed with ethyl acetate. The filter cake was dried in vacuo at 40° C. The filtrate was concentrated in vacuo and purified by flash chromatography (hexane/ethyl acetate-gradient with hexane 0-100%). The filter cake and the received purified compound of the flash chromatography were stirred together in ethyl acetate, filtered off and provided 3.95 g (11.3 mmol, 49%) of the analytically pure target compound.

1. customThe reaction mixture was evaporated in vacuo
2. stirringThe residue was stirred with ethyl acetate
3. filtrationThe resulting suspension was filtered off
4. washwashed with ethyl acetate
5. customThe filter cake was dried in vacuo at 40° C
6. concentrationThe filtrate was concentrated in vacuo
7. custompurified by flash chromatography (hexane/ethyl acetate-gradient with hexane 0-100%)
8. customThe filter cake and the received purified compound of the flash chromatography
9. stirringwere stirred together in ethyl acetate
10. filtrationfiltered off
11. customprovided 3.95 g (11.3 mmol, 49%) of the analytically pure target compound