50561-87-0

Basic information

• Product Name: 1H-Pyrazole-3-carboxylic acid, 4,5-diphenyl-, methyl ester
• CAS NO: 50561-87-0
• Molecular Formula: C17H14N2O2
• Molecular Weight: 278.31
• Mol File: 50561-87-0.mol
• Article Data: 3

Chemical Properties

• CAS DataBase Reference: 1H-Pyrazole-3-carboxylic acid, 4,5-diphenyl-, methyl ester(CAS DataBase Reference)
• NIST Chemistry Reference: 1H-Pyrazole-3-carboxylic acid, 4,5-diphenyl-, methyl ester(50561-87-0)
• EPA Substance Registry System: 1H-Pyrazole-3-carboxylic acid, 4,5-diphenyl-, methyl ester(50561-87-0)

Safety Data

• Hazardous Substances Data: 50561-87-0(Hazardous Substances Data)

Upstream product

• 908093-98-1 diazodiphenylmethane 
• 67-56-1 methanol 
• 7664-41-7 ammonia 
• 64-19-7 acetic acid 
• 7664-93-9 sulfuric acid 
• 31419-01-9 dimethyl 3,3-diphenyl-3H-pyrazole-4,5-dicarboxylate 
• 50779-86-7 dimethyl 3,4-diphenyl-4H-pyrazole-4,5-dicarboxylate 
• 62-53-3 aniline 
• 908094-04-2 phenyldiazomethane 
• 4891-38-7 phenylpropynoic acid methyl ester 

Relevant articles and documents

Intramolecular Cyclization of Vinyldiazoacetates as a Versatile Route to Substituted Pyrazoles

Vinyldiazo compounds undergo a thermal electrocyclization to form pyrazoles in yields of up to 95percent. The reactions are operationally simple, use readily available starting materials, require no intervention of a catalyst, and enable the synthesis of mono-, di- A nd tri-substituted pyrazoles. With the ability to produce highly substituted pyrazoles and the flexibility in installing various types of substituents, this method constitutes a new entry to this valuable heterocyclic scaffold and may be of interest to all branches of the chemical industry.

Regioselectivity of the thermal van Alphen–Hüttel rearrangement of 4- and 5-mono- and 4,5-disubstituted 3,3-diphenyl-3H-pyrazoles

Thermal van Alphen–Hüttel rearrangement of methyl 3,3-diphenyl-3H-pyrazole-4-carboxylate, 3,3-diphenyl-3H-pyrazole-4-carbonitrile, and methyl 5-methyl-3,3-diphenyl-3H-pyrazole-4-carboxylate involves completely regioselective migration of one phenyl group from the 3-position to N2with formation of aromatic 1H-pyrazole system. Thermal rearrangement of methyl 3,3-diphenyl-3H-pyrazole-5-carboxylate leads to the formation of methyl 4,5-diphenyl-1H-pyrazole-3-carboxylate as a result of migration of the 3-phenyl group exclusively to the C4atom and subsequent prototropic isomerization. Under analogous conditions, methyl 4-methyl-3,3-diphenyl-3H-pyrazole-5-carboxylate, methyl 5-(methanesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carboxylate, methyl 5-(benzenesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carboxylate, and dimethyl 3,3-diphenyl-3H-pyrazole-4,5-dicarboxylate have been regioselectively converted into the corresponding 4H-pyrazoles. Thermolysis of 5-(4-methylbenzenesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carbonitrile gives rise to a mixture of 1H- and 4H-pyrazoles, the former considerably prevailing, whereas the corresponding 1H-pyrazoles are formed as the only product from 5-(methanesulfonyl)- and 5-(benzenesulfonyl)-3,3-diphenyl-3H-pyrazole-4-carbonitriles.