反应详情

4-Methyl-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-benzoic acid (Intermediate 4) (2.0 g), DIPEA (4 ml) and HATU (3.05 g) were dissolved in DMF (20 ml) and stirred at room temp for 15 min. 2-Aminothiadiazole (810 mg) was added and the mixture was stirred at room temp for 18 h. The solvent was evaporated under vacuum and the residue was partitioned between ethyl acetate (250 ml) and hydrochloric acid (2N, 150 ml). The aqueous phase was extracted with ethyl acetate (2×250 ml). The combined organic extracts were dried (magnesium sulphate) and the solvent was removed under vacuum. The residue was absorbed onto silica and purified by flash column chromatography eluting with cyclohexane/ethyl acetate (4:1 then 1:1) to give the title compound (0.95 g).

1. stirringthe mixture was stirred at room temp for 18 h
2. customThe solvent was evaporated under vacuum
3. customthe residue was partitioned between ethyl acetate (250 ml) and hydrochloric acid (2N, 150 ml)
4. extractionThe aqueous phase was extracted with ethyl acetate (2×250 ml)
5. dry with materialThe combined organic extracts were dried (magnesium sulphate)
6. customthe solvent was removed under vacuum
7. customThe residue was absorbed onto silica
8. custompurified by flash column chromatography
9. washeluting with cyclohexane/ethyl acetate (4:1