反応 #2507857

反応方程式

Thionyl chloride

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

thionyl chloride

DMF

DMF

→

(Z)-3′-(2-(1-(3,4-dimethylphenyl)-3-methyl-5-oxo-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-2′-hydroxybiphenyl-3-carbonyl chloride

収率 96.0%

溶媒

heptane

THF

反応条件

後処理

1. 1
   その他The precipitation of acyl chloride
2. 2
   workup.WAITstarted in half an hour
3. 3
   workup.ADDITIONheptane (90 mL) was added
4. 4
   workup.STIRRINGThe thick reaction suspension was stirred for further half an hour
5. 5
   ろ過filtrated

実験手順

Thionyl chloride (5 mL, 68.5 mmol) was added to a solution of pure 3′-{N′-[1-(3,4-Dimethylphenyl)-3-methyl-5-oxo-1,5-dihydro-pyrazol-4-ylidene]hydrazino}-2′-hydroxybiphenyl-3-carboxylic acid (Eltrombopag form I) (5 g, 11 mmol) in dry THF (75 mL) followed by addition of DMF (0.5 mL) at room temperature in three-necked flask. The reaction mixture was stirred for one hour and additional thionyl chloride (5 mL, 68.5 mmol) and DMF (0.5 mL) were added. The precipitation of acyl chloride started in half an hour and heptane (90 mL) was added. The thick reaction suspension was stirred for further half an hour, filtrated and washed with 2×50 mL of heptane yielding 5 g of (Z)-3′-(2-(1-(3,4-dimethylphenyl)-3-methyl-5-oxo-1H-pyrazol-4(5H)-ylidene)hydrazinyl)-2′-hydroxybiphenyl-3-carbonyl chloride (Yield: 96%); (HPLC: 95%), that was immediately used for the next step.

出典