反应详情

In analogy to the procedure described for example 2 a], 5-(4-trifluoromethyl-phenyl)-1H-pyrazole-3-carboxylic acid ethyl ester (PCT Int. Appl. (2003), WO 2004000785 A2) was reacted with methyl iodide in the presence of potassium hydroxide to give 2-methyl-5-(4-trifluoromethyl-phenyl)-2H-pyrazole-3-carboxylic acid ethyl ester and 1-methyl-5-(4-trifluoromethyl-phenyl)-1H-pyrazole-3-carboxylic acid ethyl ester, both as colorless crystals.