反应详情

To the residue dissolved in 100 ml 95% ethanol is added sodium dithionite (9.4 g, 54 mmol) dissolved in 60 ml water and 15 ml concentrated ammonium hydroxide. After refluxing for 5 minutes, portions of sodium dithionite (1 g in 10 ml water and 2 ml ammonium hydroxide) are added until the orange nitroaniline color disappears. The reaction mixture is reduced to one-half volume by evaporation, basified with 20 ml 10% sodium hydroxide, and extracted with chloroform (X 5). The chloroform washings are dried (Na2SO4) and evaporated. The residue, 3.3 g (16.1 mmol) of the thiopseudourea from Example 1, part D, 6 drops of acetic acid, and 50 ml of methanol are refluxed for 2 hours. After stirring overnight at room temperature, the product crystallizes out, is filtered off and digested with 50 ml hot methanol to yield the title compound, 2.77 g, m.p. 228°-235°(d).

1. temperatureAfter refluxing for 5 minutes
2. customThe reaction mixture is reduced to one-half volume by evaporation
3. extractionextracted with chloroform (X 5)
4. dry with materialThe chloroform washings are dried (Na2SO4)
5. customevaporated
6. customthe product crystallizes out
7. filtrationis filtered off