72606-92-9

Upstream product

• 74-96-4 ethyl bromide 
• 846022-60-4 1-phenyl-5-(4-methoxyphenyl)-3-hydroxypyrazole 
• 113463-18-6 C₁₆H₁₆N₂O₂ 
• 100-63-0 phenylhydrazine 
• 832-01-9 methyl p-methoxycinnamate 

Downstream Products

• 1338378-18-9 4-chloro-3-ethoxy-5-(4-methoxyphenyl)-1-phenyl-1H-pyrazole 

Relevant academic research and scientific papers

DMF-catalyzed direct and regioselective C-H functionalization: Electrophilic/nucleophilic 4-halogenation of 3-oxypyrazoles

A novel, straightforward, and highly regioselective 4-chlorination of 3-oxypyrazole derivatives in boiling thionyl chloride (SOCl2) in the presence of catalytic N,N-dimethylformamide (DMF) has been developed. This reaction likely proceeds through a DMF-catalyzed electrophilic/nucleophilic chlorination mechanism and involves electrophilic attack by SOCl2 and nucleophilic substitution by Cl- as the key steps. Based on this mechanism, the corresponding 4-bromination and 4-iodination of 3-oxypyrazoles have also been achieved in good yield by adding Br- and I -, respectively, to the reaction system. This halogenation method enables quick access to many original 4-halo-3-oxypyrazole series. A novel DMF-catalyzed electrophilic/nucleophilic 4-halogenation of 3-oxypyrazole derivatives has been developed. This halogenation procedure provides quick access to many novel 4-halo-3-oxypyrazole series.