New Synthesis and Properties of 3-Alkyl-, 3-Chloroalkyl-, 3-Perfluoroalkyl-, and 3-Aryl-1-methyl-(5-halo) pyrazoles from Chloro (bromo) vinyl Ketones and N, N- …

GG Levkovskaya, GV Bozhenkov, LI Larina…

Index: Levkovskaya; Bozhenkov; Larina; Mirskova Russian Journal of Organic Chemistry, 2002 , vol. 38, # 10 p. 1501 - 1506

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Citation Number: 23

Abstract

Abstract A new regioselective heterocyclization was revealed in the reaction of 2-chloro-and 2, 2-dichloro (bromo) vinyl ketones with N, N-dimethylhydrazine to afford 3-substituted 1- methyl (5-halo) pyrazoles. The reaction is accompanied by elimination of methyl halide and formation of up to 90% of N, N, N-trimethylhydrazinium halide as the second product.