Reacción #87891

Ecuación de reacción

3′-{N′-[1-(3,4-dimethylphenyl)-3-methyl-5-oxo-1,5-dihydro-pyrazol-4-ylidene]hydrazino}-2′-methoxybiphenyl-3-carboxylic acid

acetic acid

→

3′-{N′-[1-(3,4-dimethylphenyl)-3-methyl-5-oxo-1,5-dihydro-pyrazol-4-ylidene]hydrazino}-2′-hydroxybiphenyl-3-carboxylic acid

Disolventes

hydrobromic acid

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturaheated
2. 2
   Temperaturaunder reflux for about 60 hours
3. 3
   ConcentraciónThe reaction mixture was concentrated under vacuum to a thick residue
4. 4
   workup.ADDITIONWater (40 mL) was added
5. 5
   FiltraciónThe mixture was filtered
6. 6
   Otroto give an orange solid, which
7. 7
   Lavadowas washed with water (25 mL)
8. 8
   Otrodried in an oven at 55° C. about to about 60° C. for about 12 hours

Procedimiento

A solution of 3′-{N′-[1-(3,4-dimethylphenyl)-3-methyl-5-oxo-1,5-dihydro-pyrazol-4-ylidene]hydrazino}-2′-methoxybiphenyl-3-carboxylic acid (4 g), prepared as in Example 3, in 48% aqueous hydrobromic acid (35 mL) and glacial acetic acid (35 mL) was stirred and heated under reflux for about 60 hours. The reaction mixture was concentrated under vacuum to a thick residue. Water (40 mL) was added and basified to pH 7-8 using saturated solution of sodium bicarbonate (20 mL). The mixture was filtered to give an orange solid, which was washed with water (25 mL) and dried in an oven at 55° C. about to about 60° C. for about 12 hours.

Fuente