Synthesis of some trifluoromethyl substituted 1??methylpyrazoles

…, TIN Ayudhya, S Tantayanon

Index: Pavlik, James W.; Ayudhya, Theppawut Israsena Na; Tantayanon, Supawan Journal of Heterocyclic Chemistry, 2003 , vol. 40, # 6 p. 1087 - 1089

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Citation Number: 12

Abstract

Abstract The major products from the reaction of β-alkoxyvinyl trifluoromethyl ketones 1a-c with methylhydrazine (2) in absolute ethanol are the 3-(trifluoromethyl)-substituted-1- methylpyrazoles 3a-3c with lesser amounts of the 5-(trifluoromethyl)-substituted products 4a- 4c and 5a-5c. Carrying out the reaction in non-polar, aprotic solvents can further enhance the regioselectivity favoring the 3-(trifluoromethyl)-substituted isomers.