反应详情

温度

0 °C

Potassium hydroxide (0.5 g, 0.0096 mole) is added in one portion to a stirred 0° C. solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxycinnamic acid hydrazide (2.8 g, 0.0096 mole) and carbon disulfide (1.7 g, 0.022 mole) in absolute ethanol (15.0 ml). The resulting mixture is stirred 1.5 hours at 0° C. before heating to reflux for four hours. The solution is cooled and the solvent is removed in vacuo. The residue is dissolved in water (50 ml) and washed with ether (20 ml). The aqueous layer is made acidic with aqueous 2M HCl and the product extracted with a 1:1 mixture of ethyl acetate/ether. The combined organic extracts are washed with saturated aqueous NaCl and dried over MgSO4. Filtration and concentration gives a solid which is recrystallized from ethyl acetate/hexane to give 1.4 g (3.2 g theor., 44%) desired product, mp 209.5° C.

1. temperaturebefore heating
2. temperatureto reflux for four hours
3. temperatureThe solution is cooled
4. customthe solvent is removed in vacuo
5. dissolutionThe residue is dissolved in water (50 ml)
6. washwashed with ether (20 ml)
7. extractionthe product extracted with a 1:1 mixture of ethyl acetate/ether
8. washThe combined organic extracts are washed with saturated aqueous NaCl
9. dry with materialdried over MgSO4
10. filtrationFiltration and concentration
11. customgives a solid which
12. customis recrystallized from ethyl acetate/hexane