反应详情

3′-[(2Z)-[1-(3,4-dimethylphenyl)-1,5-dihydro-3-methyl-5-oxo-4H-pyrazol-4-ylidene]hydrazino]-2′-hydroxy-[1,1′-biphenyl]-3-carboxylic acid, 8 g of crude orange solid, was suspended at room temperature in ethanol (800 ml) under a nitrogen atmosphere. Ethanolamine (2.2 ml, −2 molar equivalents) was added via syringe over 5 minutes. The resulting dark red suspension was stirred at room temperature for 45 hours and the solid isolated by filtration, washed with ethanol (10 ml×2) and dried at 50° C. in a vacuum oven over night to yield 9.83 g (96% yield) of the title compound. NMR similar to Example 1; ethanol content 1.3% w/w but no THF present.

1. customthe solid isolated by filtration
2. washwashed with ethanol (10 ml×2)
3. customdried at 50° C. in a vacuum oven over night