In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 42122-44-1 as follows. category: esters-buliding-blocks
Example 2.42- (4-Fluoro-phenvl)-6-methanesulfonvl-3- (4-methanesulfonyl-phenyl)-pyrazolof 1. 5-blpvridazine(i) 2- (4-Fluoro-phenvl)-6-methvlsulfanvl-pyrazolo1, 5-blpvridazine-3-carboxvlic acid methyl ester Solidt-butoxycarbonyl-O-mesitylenesulfonylhydroxylamine’ (7. 8g) was added portionwise with stirring to TFA (25mL) over 10min then stirred for a further 20 minutes. The solution was poured onto ice(-200mL) and left until the ice melted. The resulting white solid was filtered off, washed with water, and dissolved in DME(100mL). The solution was dried over 4A mol. sieves for 1.5 hours, filtered then added to a solution of3-methylthio-pyridazine2 (2.6g) indichloromethane (35mL) and the reaction stirred at room temperature for 20h. The intermediate salt was isolated by filtration as light brown crystals (3. 87g), suspended in acetonitrile(100mL) and methyl3- (4-fluoro-phenyl)-prop-2-ynoic acid (2. 02g) added. 1,8- Diazabicyclo [5.4. 0] undec-7-ene (2. 1mL) was added dropwise and the reaction was stirred at room temperature for 20 hours. The resulting crystalline precipitate was filtered off, washed and dried (770mg). Concentration of the filtrate gave a second crop (430mg). The residues were partioned between water and ethyl acetate(100mL each) and the aqueous layer was extracted with ethyl acetate (20mL). The combined organics were washed with water, brine and dried. Removal of solvent gave a brown oil which was purified by flash chromatography on silica (300g) eluting with cyclohexane/ethyl acetate (3: 1) to give a further quantity of product (247mg). The three crops were combined to give the title compound (1.45g) as a light brown solid.
According to the analysis of related databases, 42122-44-1, the application of this compound in the production field has become more and more popular.
Reference:
Patent; GLAXO GROUP LIMITED; WO2005/48999; (2005); A2;,
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