反应详情

3′-Amino-2′-hydroxy-biphenyl-3-carboxylic acid hydrobromide 1f (310 mg, 1.0 mmol) was dissolved in hydrochloric acid (3.4 mL, 1 mol/L) upon cooling by an ice-water bath, followed by dropwise addition of 1.2 mL of aqueous sodium nitrite (73 mg, 1.05 mmol). After the mixture was reacted for 10 minutes, 2-(3,3-dimethyl-indan-5-yl)-5-methyl-2,4-dihydro-pyrazol-3-one 8i (218 mg, 0.9 mmol), sodium bicarbonate (1.26 g, 15 mmol) and 4.4 mL of ethanol were added successively. The reaction mixture was reacted at room temperature for 10 hours. The reaction was monitored by TLC until the disappearance of the starting materials. The mixture was filtered and the filter cake was washed with 20 mL of water and then dissolved in 20 mL of water. Upon cooling by an ice-water bath, the mixture was adjusted to pH<5 with concentrated hydrochloric acid, filtered and dried to obtain the title compound 3′-{N′-[1-(3,3-dimethyl-indan-5-yl)-3-methyl-5-oxo-1,5-dihydro-pyrazol-4-ylidene]-hydrazino}-2′-hydroxy-biphenyl-3-carboxylic acid 30 (500 mg, yield 94%) as a yellow solid.

1. temperatureupon cooling by an ice-water bath
2. customAfter the mixture was reacted for 10 minutes
3. customThe reaction mixture was reacted at room temperature for 10 hours
4. filtrationThe mixture was filtered
5. washthe filter cake was washed with 20 mL of water
6. dissolutiondissolved in 20 mL of water
7. temperatureUpon cooling by an ice-water bath
8. filtrationfiltered
9. customdried