109072-62-0

Upstream product

• 3815-34-7 2,2-dimethyl-1-phenyl-1,3-butanedione 
• 3619-22-5 p-toluic hydrazide 
• 109072-63-1 4,5-dihydro-4,4-dimethyl-5-methylene-3-phenyl-1-p-toluoyl-1H-pyrazole 

Downstream Products

• 109072-63-1 4,5-dihydro-4,4-dimethyl-5-methylene-3-phenyl-1-p-toluoyl-1H-pyrazole 

Relevant academic research and scientific papers

Unusual Reactions between Some 1-Aroyl-4,5-dihydro-4,4-dimethyl-5-methylene-1H-pyrazoles and Ketenes

5-Methylene-4,5-dihydropyrazoles 1a-d react with diphenylketene (DPK), affording the pyrazolyl-3,3-diphenyl-2-propenyl benzoates 2a-d, very likely via the corresponding pyrazolyl-enol esters 7 as intermediates.By acid hydrolysis of 2 the (diphenyloxopropyl)pyrazole derivative 3 in its enol form is isolated, whereas by cycloaddition with 4-methylbenzonitrile oxide the spiro compound 4 is obtained. 5-Methylene-4,5-dihydropyrazoles 1a-c and 1g also react with dichloroketene (DCK) to give the corrresponding 5-hydroxypyrazolines 5.The structure of 2b has also been confirmed by X-ray crystallography.