반응 #59692

반응 방정식

4-Methyl-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-benzoic acid

Intermediate 21

4-Methyl-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-benzoic acid

DIPEA

HATU

2-Aminothiazole

→

4-methyl-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-N-(thiazol-2-yl)-benzamide

수율 65.5%

용매

DMF

반응 조건

후처리

1. 1
   workup.STIRRINGthe reaction stirred at room temperature for 18 hours
2. 2
   기타The solvent was evaporated under vacuum
3. 3
   기타the reaction partitioned between ethyl acetate (250 ml) and water (50 ml)
4. 4
   세척The organic phase was washed with hydrochloric acid (2N, 50 ml) and aqueous sodium bicarbonate (1M, 50 ml)
5. 5
   건조dried (magnesium sulphate)
6. 6
   기타the solvent evaporated under vacuum
7. 7
   기타The residue was absorbed onto silica
8. 8
   기타purified by flash column chromatography
9. 9
   세척eluting with cyclohexane/ethyl acetate (4:1)
10. 10
    기타The solvent was evaporated from the product fractions under vacuum

실험 절차

4-Methyl-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-benzoic acid (Intermediate 21) (2.0 g, 7.63 mmol), DIPEA (4 ml, 22.89 mmol) and HATU (3.05 g, 8.02 mmol) were dissolved in DMF (20 ml) and stirred at room temperature for 15 mins. 2-Aminothiazole (801 mg, 8.01 mmol) was added and the reaction stirred at room temperature for 18 hours. The solvent was evaporated under vacuum and the reaction partitioned between ethyl acetate (250 ml) and water (50 ml). The organic phase was washed with hydrochloric acid (2N, 50 ml) and aqueous sodium bicarbonate (1M, 50 ml), then dried (magnesium sulphate) and the solvent evaporated under vacuum. The residue was absorbed onto silica and purified by flash column chromatography eluting with cyclohexane/ethyl acetate (4:1). The solvent was evaporated from the product fractions under vacuum to give 4-methyl-3-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-N-(thiazol-2-yl)-benzamide (1.72 g).

출처