108718-62-3

Upstream product

• 59-88-1 phenylhydrazine hydrochloride 
• 4023-82-9 4-nitrobenzoylacetone 
• 100-63-0 phenylhydrazine 
• 109157-01-9 3-Methyl-5-(4'-nitrophenyl)-1-phenylpyrazole-4-carboxylic acid 
• 34292-35-8 4-(4-nitro-phenyl)-but-3-en-2-one-phenylhydrazone 

Relevant academic research and scientific papers

Microwave-mediated pyrazole fluorinations using selectfluor

Microwave-mediated electrophilic fluorinations and a new single-pot condensation en route to ring-fluorinated pyrazoles were examined: chemical equation represented The monofluorination by these methods was successful for a variety of pyrazoles, with yields ranging from 13% to 75%. While electrophilic aromatic fluorination of 3-CF3 pyrazoles proved largely ineffective, development ofa single-pot process overcame this limitation. The microwave-mediated reaction is regioselective; ring fluorination of the heterocycle occurs preferentially over phenyl and alkyl substituents. Alkyl side chain fluorination, when desired, can be modulated by reactant ratios. The single-pot method, which involves acid catalysis by H-TEDA, produces 4-fluoropyrazoles products.

Scope and limitations in the regioselective synthesis of 1,3,5-trisubstituted pyrazoles from β-amino enones and hydrazine derivatives. 13C-chemical shift prediction rules for 1,3,5-trisubstituted pyrazoles

β-amino enones react with hydrazine derivatives to give regioselectively 1,3,5-trisubstituted pyrazoles. The synthetic method only presents limitations when the β-substituent of the enone and the hydrazine substituent are bulky or possess an electron withdrawing character. Comparison of the 13C-NMR spectra of the seventy pyrazoles allowed us to estimate a 13C-chemical shift prediction rule for 1,3,5-trisubstituted pyrazoles, with deviations of less than ± 1 ppm.

Oxidative Cyclization of Arylhydrazones of Chalcones and Benzalacetones to Pyrazoles by Thianthrene Cation Radical

Phenyl-, (p-nitrophenyl)-, and (2,4-dinitrophenyl)hydrazones of chalcone (benzalacetophenone), benzalacetone, and of some of their derivatives undergo oxidative cyclization in reactions with thianthrene cation radical perchlorate.The products are, respect