Sa. Voznesenskii et al., AN UNEXPECTED REACTION OF 3-ARYL-2-PYRAZOLIN-5-YLACETOHYDRAZIDES WITHCHLORINE - FORMATION OF 3-ARYL-4-CHLORO-5-TRICHLOROMETHYLPYRAZOL, Mendeleev communications, (1), 1998, pp. 14-15
In attempting to synthesize 3-aryl-2-pyrazolin-5-ylacetyl chlorides by
chlorination of the respective hydrazides, 3-aryl-4-chloro-5-trichlor
omethylpyrazoles have been obtained; a probable mechanism for the tran
sformation is discussed.