반응 #1250

반응 방정식

product

Ethyl 2,4-dioxo-3-oximino-4-(2,4,6-trimethylphenyl)butanoate

hydrochloric acid

methyl hydrazine

→

title compound

수율 78.9%

Ethyl 4-amino-1-methyl-5-(2,4,6-trimethylphenyl)pyrazole-3-carboxylate

수율 78.9%

용매

methanol

반응 조건

후처리

1. 1
   농축concentrated
2. 2
   기타The resulting residue was partitioned between water and ethyl acetate
3. 3
   기타The organic phase was separated
4. 4
   세척washed once with brine
5. 5
   workup.ADDITIONThe ethyl acetate solution was then mixed with 100 mL of water
6. 6
   workup.ADDITIONSolid Na2S2O4 in excess was added in small portion until TLC
7. 7
   기타The organic phase was separated
8. 8
   세척washed with water and brine
9. 9
   건조dried over Na2SO4
10. 10
    기타Evaporation

실험 절차

To a solution of the product of step B (4.0 g, 13.8 mmol) and 1.6 mL of 12N hydrochloric acid in 100 mL of methanol was added dropwise 0.63 g of methyl hydrazine at 0° C. The reaction mixture was stirred at room temperature 4 hours, and then concentrated. The resulting residue was partitioned between water and ethyl acetate. The organic phase was separated and washed once with brine. The ethyl acetate solution was then mixed with 100 mL of water. Solid Na2S2O4 in excess was added in small portion until TLC showed completion of the reduction. The organic phase was separated, washed with water and brine, and dried over Na2SO4. Evaporation gave 3.1 g of the title compound as a foam.

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