63777-01-5

Upstream product

• 67-64-1 acetone 
• 4845-49-2 1,3-diphenyl-5-oxo-4,5-dihydro-1H-pyrazole 
• 59-88-1 phenylhydrazine hydrochloride 
• 94-02-0 ethyl 3-oxo-3-phenylpropionate 
• 100-63-0 phenylhydrazine 

Downstream Products

• 63777-03-7 6-methoxy-4,4-dimethyl-1,3-diphenyl-1,4,5,6-tetrahydro-pyrano[2,3-c]pyrazole 
• 63777-07-1 6-isobutoxy-4,4-dimethyl-1,3-diphenyl-1,4,5,6-tetrahydro-pyrano[2,3-c]pyrazole 
• 1643536-96-2 (R,Z)-4-(5-nitro-4-phenylpentan-2-ylidene)-2,5-diphenyl-2,4-dihydro-3H-pyrazol-3-one 
• 77196-32-8 4,5-dihydroxy-1,3-diphenylpyrazole 
• 87277-56-3 1,3-Diphenyl-4,6,6-trimethyl-1,6-dihydropyrano<2,3-c>pyrazole 
• 84263-08-1 2,2-dimethyl-5,7-diphenyl-1-oxa-5,6-diazaspiro<2.4>hept-6-en-4-one 
• 63777-05-9 6-ethoxy-4,4-dimethyl-1,3-diphenyl-1,4,5,6-tetrahydro-pyrano[2,3-c]pyrazole 
• 63777-09-3 6-isopropoxy-4,4-dimethyl-1,3-diphenyl-1,4,5,6-tetrahydro-pyrano[2,3-c]pyrazole 

Relevant academic research and scientific papers

Regioselective N-Addition/Substitution Reaction of α-Alkylidene Pyrazolinones with Propargyl Sulfonium Salts to Construct Allylthio-Containing Pyrazolones

The regioselective N-addition/substitution reaction between α-alkylidene pyrazolinones and propargyl sulfonium salts has been developed to construct functionalized allylthio-containing pyrazolones with moderate to excellent yields. α-Alkylidene pyrazolinones act as N-nucleophilic agents which are distinguished from reported C-nucleophilic reactions. Excellent regioselectivity, readily available starting materials, the broad range of substrates, gram-scale synthesis, and simple operation illustrate the synthetic advantages of this new reaction pathway.

Combined inorganic base promoted N-addition/[2,3]-sigmatropic rearrangement to construct homoallyl sulfur-containing pyrazolones

The first sequentially combined inorganic base promoted N-addition/[2,3]-sigmatropic rearrangement reaction of α-alkylidene pyrazolinones and propargyl sulfonium salts has been reported to construct homoallyl sulfur-containing pyrazolones with moderate to excellent yields. α-Alkylidene pyrazolinones function as N-nucleophilic agents distinguished from the reported C-addition reactions. Propargyl sulfonium salts were first involved in the [2,3]-sigmatropic rearrangement protocol differentiated from the well-established annulation reactions. The excellent regioselectivity, the broad scope of substrates, gram-scale synthesis and convenient transformation embody the synthetic superiority of this cascade process.

Direct and enantioselective vinylogous michael addition of α-alkylidenepyrazolinones to nitroolefins catalyzed by dual cinchona alkaloid thioureas

While several protocols exist for the asymmetric functionalization of pyrazolinones at the α-position relying on nucleophilic addition or annulation procedures, use of α-alkylidene electron-rich analogues in asymmetric vinylogous coupling to carbon electrophiles is substantially an uncharted domain. We now report, for the first time, that alkylidenepyrazolinones carrying an enolizable carbon at the γ-position efficiently participate in direct and asymmetric, catalytic vinylogous Michael-type additions to nitroolefins providing the expected adducts in high yields, with complete γ-site selectivity and with extraordinary levels of enantio-, diastereo-, and geometrical selectivities. Both enantiomeric adducts were equally accessed by employing a quasi-enantiomeric quinine- or quinidine-based thiourea catalyst pair.

A New Synthesis of 4,5-Dihydroxy-pyrazoles

1-Aryl-pyrazolin-5-ones 1 are converted by Knoevenagel condensation with acetone or by reaction with 2,2-dimethyl-1,3-dioxolane 6 to 1-aryl-4-isopropyliden-pyrazolin-5-ones 2.The compounds 2 are epoxidized by hydrogen peroxide forming the spiro-epoxides 3, which can be cleaved to 4,5-dihydroxy-pyrazoles 4 under acidic conditions. 4-Acetoxy-5-hydroxy-pyrazoles 13 are formed directly, when 3 are cleaved in presence of acetic anhydride.The 3,3',3'-trimethyl-1-(4-nitro-phenyl)-pyrazolin-4-spiro-2'-oxiran-5-one 3b undergoes rearrangement to the 1,3-dioxolopyrazole 12.

Studies on 2,5-Diaryl-2,4-dihydro-3H-pyrazol-3-ones. I. Synthesis of Highly Substituted 1H-Indazoles Using Tautomeric 2,5-Diaryl-2,4-dihydro-3H-pyrazol-3-ones

The reaction of 2-aryl-5-phenyl-2,4-dihydro-3H-pyrazol-3-ones (1) with acetone gave 2-aryl-4-(1-methylethylidene)-5-phenyl-2,4-dihydro-3H-pyrazol-3-ones (2) in nearly quantitative yields, and these products reacted further with acetone in the presence of triethylamine (NEt3) as a catalyst to give 1-aryl-4,6,6-trimethyl-3-phenyl-1,6-dihydropyranopyrazoles (3).Reaction of 3 with dimethyl acetylenedicarboxylate (DMAD) or diethyl acetylenedicarboxylate (DEAD) in dimethylformamide (DMF) at reflux gave 1-aryl-4-methyl-3-phenyl-1H-indazole-6,7-dicarboxylate (7) in high yields.Thus, a new and convenient route for the synthesis of highly substituted 1H-indazoles has been developed.Keywords - tautomerism; 2,4-dihydro-3H-pyrazol-3-one; 1,6-dihydropyrano-pyrazole; 1H-indazole; dimethyl acetylenedicarboxylate; diethyl acetylenedicarboxylate; condensation; Diels-Alder reaction