反应详情

温度

-30 °C

4-t-butoxycarbonylaminobenzotrifluoride (3.90 g) was dissolved in THF. At −50° C., t-butyl lithium (30 ml) was added dropwise thereto. The mixture was stirred for 3 hours with keeping at −50° C. Carbon dioxide gas was bubbled into this mixture under stirring (the temperature increased to about −30° C.). The solvent was distilled out. The back-extractration of the residue was 2N NaOH-ether mixture solution was carried out. The aqueous layer was acidified by adding 2N HCl, extracted with ether, washed and dried over. In addition, the layer containing ether was washed, dried over, filtered and concentrated after combining the said layer containing ether to give the crude compound. Such crude compound was dissolved in ether. A solution of diazomethane in ether was added thereto until the reaction solution became yellow. The reaction solution was concentrated and purified on silica gel column chromatography (hexane:AcOEt=20:1→10:1) to give the title compound (3.80 g) having the following physical data.

1. customwith keeping at −50° C
2. customCarbon dioxide gas was bubbled into this mixture
3. stirringunder stirring (the temperature
4. distillationThe solvent was distilled out
5. additionby adding 2N HCl
6. extractionextracted with ether
7. washwashed
8. customdried over
9. additionIn addition, the layer containing ether
10. washwas washed
11. customdried over,
12. filtrationfiltered
13. concentrationconcentrated
14. additioncontaining ether
15. customto give the crude compound
16. concentrationThe reaction solution was concentrated
17. custompurified on silica gel column chromatography (hexane:AcOEt=20:1→10:1)