22877-14-1

Upstream product

• 1775-98-0 2'-hydroxy-5'-methylchalcone 
• 100-63-0 phenylhydrazine 
• 176221-03-7 3-(2-hydroxy-5-methylphenyl)-1-phenyl-2-propene-1-ketone 
• 59-88-1 phenylhydrazine hydrochloride 
• 1775-98-0 (E)-1-(2-hydroxy-5-methylphenyl)-3-phenylprop-2-en-1-one 
• 22219-26-7 2'-hydroxy-5'-methylchalkone dibromide 

Downstream Products

• 37741-76-7 2-(1,5-diphenyl-1H-pyrazol-3-yl)-4-methylphenol 

Relevant academic research and scientific papers

Unexpected ring opening of pyrazolines with activated alkynes: synthesis of 1H-pyrazole-4,5-dicarboxylates and chromenopyrazolecarboxylates

1H-Pyrazole-4,5-dicarboxylates and chromenopyrazole carboxylates were prepared by reacting pyrazolines with activated alkynes under neat conditions without a catalyst. The products were formed via unexpected ring opening of pyrazolines with the elimination of styrene/ethylene. These types of transformations are unknown and the products formed were confirmed using their spectral/analytical data. In addition, the structures of compounds 5e and 5n were confirmed by single-crystal X-ray analysis. Control experiments were conducted to support the proposed reaction mechanism.

Selective O-deallylation of dihydropyrazoles by molecular iodine in the presence of active N-allyl and formyl groups

Selective O-deallylation of dihydropyrazoles has been achieved by use of iodine (10 mol%) in PEG-400 as ecofriendly solvent. Iodine (10 mol%) in dimethyl sulfoxide at 100 C also afforded O-deallylation with aromatization compatible with highly reactive N-

Synthesis of pyrazoline and isoxazoline in triethanolamine medium

Reactions of chalcones 1a-u with phenylhydrazine and hydrazine hydrate give pyrazolines 2a-u and with hydroxylamine hydrochloride yield isoxazolines 3a-c in triethanolamine medium. The structures of products are established by melting points, chemical studies and spectral data (IR and 1HNMR).

SYNTHESIS OF SOME ISOMERIC PYRAZOLES

The syntheses of 3-o-hydroxyphenyl-1,5-diphenylpyrazoles (III) and 1,3-diphenyl-5-o-hydroxyphenylpyrazoles (V) by the oxidation of corresponding pyrazolines (II) with manganese dioxide and by the reaction of phenylhydrazine with 2'-hydroxychalcone dibromi

Action of Phenylhydrazine Hydrochloride on Chalkone Dibromides in Dimethylformamide

Chalkone dibromides (II) when treated with phenylhydrazine hydrochloride in DMF do not give the expected pyrazoles, but afford 3,5-diaryl-1-phenylpyrazolines (III) which are the normal products of chalkones (I) and phenylhydrazine hydrochloride in DMF.