4-Ethynyl-1,3,5-trimethylpyrazole and 3,5-diethynyl-1-methylpyrazole have been synthesized by the reaction of the corresponding methyl N-methyl-pyrazolyl ketones with PCl5 followed by dehydrochlorination. 4-Butadiynyl-1,3,5-trimethylpyrazole has been obtained similarly from 4-acetoacetyl-1,3,5-trimethylpyrazole. The N-substituted pyrazolylacetylenes have been subjected to the Chodkiewicz-Cadiot reaction and to dehydrocondensation. The IR spectra of the acetylene derivatives of pyrazole synthesized are discussed.
ASJC Scopus subject areas
- Organic Chemistry