反应详情

A mixture of ethyl 6-methyl-2,4-dioxocyclohexane-1-carboxylate, 7b (1.43 g, 7.2 mmole) and 5-methyl-2-aminobenzenethiol, 6 (X=Me, 1.0 g, 7.2 mmole) in DMSO (10 mL) is placed in a preheated heating mantle. The reaction mixture is stirred and refluxed for 0.5 h. Upon cooling, the reaction mixture forms a solid. The crystals are filtered and the remaining mother liquid is poured into cold water, whereupon further precipitation occurs. Each precipitate is separately recrystallized twice from EtOH and proves to be identical. An analytical sample of 4i, (R=Me), mp 224° C. occurs as light orange crystals; yield: 0.50 (21.9%).

1. temperaturerefluxed for 0.5 h
2. temperatureUpon cooling
3. filtrationThe crystals are filtered
4. additionthe remaining mother liquid is poured into cold water, whereupon further precipitation
5. customEach precipitate is separately recrystallized twice from EtOH