反应详情

To a solution of 2,4-dichloro-3-aminophenol hydrochloride (GLSynthesis, 7.70 g, 35.9 mmol, 1.0 eq.) in acetone is added powdered potassium hydroxide 85% (9.48 g, 143.6 mmol, 4.0 eq.) in small portions. Then, dimethyl sulfate (5.13 ml, 53.9 mmol, 1.5 eq.) is added at such a rate that the internal temperature does not rise above 30° C. After 1 h stirring at room temperature water (50 ml) is added and stirring is continued for another hour. The solvent is evaporated and the residue is distributed between ethyl acetate (150 ml) and water (100 ml). The organic layer is isolated, dried over Na2SO4 and evaporated to give a yellow oil. Kugelrohr distillation affords the desired product as a colorless oil: b.p. 150° C./0.3 mbar, HPLC: tR=5.61 min (purity: 90%, gradient A), 400 MHz 1H-NMR (CDCl3) δ: 3.87 (s, 3H, OMe), 4.49 (br s, 2H, NH2), 6.30 (d, 1H, Ar—H4), 7.11 (d, 1H, Ar—H5).

1. customdoes not rise above 30° C
2. additionis added
3. waitis continued for another hour
4. customThe solvent is evaporated
5. customThe organic layer is isolated
6. dry with materialdried over Na2SO4
7. customevaporated
8. customto give a yellow oil
9. distillationKugelrohr distillation