6831-89-6Relevant academic research and scientific papers
Ultrasound assisted synthesis of 1,5-disubstituted pyrazole using Cu(I) catalyst
Pise, Ashok S.,Burungale, Arvind S.,Devkate, Santosh S.
, p. 575 - 579 (2020/02/06)
A new efficient and convenient approach towards the synthesis of pyrazole is described. The α,β-unsaturated cyanoesters were obtained from substituted benzaldehyde and ethyl cyanoacetate by reported methods. 1,5-Disubstituted pyrazoles were synthesized fr
Copper-mediated tandem ring-opening/cyclization reactions of cyclopropanols with aryldiazonium salts: Synthesis of: N -arylpyrazoles
Liu, Jidan,Xu, Erjie,Jiang, Jinyuan,Huang, Zeng,Zheng, Liyao,Liu, Zhao-Qing
supporting information, p. 2202 - 2205 (2020/02/26)
A general method for the synthesis of structurally diverse N-arylpyrazoles from readily available cyclopropanols and aryldiazonium salts is disclosed. The reaction was conducted at room temperature within minutes with a broad substrate scope and excellent regioselectivity.
Preparation method of polysubstituted pyrazole compound
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Paragraph 0094-0099, (2021/01/04)
The invention relates to the technical field of organic synthesis, in particular to a preparation method of a polysubstituted pyrazole compound. The method comprises the following steps: carrying outa condensation reaction on alkynyl ketone compounds and
Ruthenium-catalyzed formation of pyrazoles or 3-hydroxynitriles from propargyl alcohols and hydrazines
Kaufmann, Julia,J?ckel, Elisabeth,Haak, Edgar
supporting information, p. 91 - 101 (2019/07/09)
Functionalized pyrazoles are generated from secondary propragyl alcohols and hydrazines in a ruthenium-catalyzed cascade process, consisting of redox isomerization, Michael addition, cyclocondensation and dehydrogenation steps. The same bifunctional catalyst mediates the conversion of tertiary propargyl alcohols with hydrazine to 3-hydroxynitriles via anti-Markovnikov hydroamination followed by elimination of ammonia.
Cycloisomerization of acetylenic oximes and hydrazones under gold catalysis: Synthesis and cytotoxic evaluation of isoxazoles and pyrazoles
Jeyaveeran,Praveen, Chandrasekar,Arun,M Prince,Perumal
, p. 73 - 83 (2016/02/09)
The synthesis of substituted isoxazoles and pyrazoles through a general cycloisomerization methodology has been reported. The capability of gold(III) chloride to promote cycloisomerization of both α, β-acetylenic oximes and α, β-acetylenic hydrazones is t
Oxone-mediated facile access to substituted pyrazoles
Kashiwa, Mitsuhiro,Kuwata, Yoshiyuki,Sonoda, Motohiro,Tanimori, Shinji
, p. 304 - 311 (2015/12/30)
An Oxone-mediated transition-metal-free oxidative C-N bond formation has been achieved for the regioselective synthesis of substituted pyrazoles. The reactions accompany the chelation-controlled ortho-oxidation of N-substituted aromatic ring to provide ph
Novel crown ether functionalized imidazolium-based acidic ionic liquid catalyzed synthesis of pyrazole derivatives under solvent-free conditions
Patil, Dayanand,Chandam, Dattatraya,Mulik, Abhijeet,Jagdale, Suryabala,Patil, Prasad,Deshmukh, Madhukar
, p. 6843 - 6858 (2015/08/18)
Abstract An innovatively designed novel crown ether functionalized imidazolium-based reusable acidic ionic liquid [crown ether MIm] [HSO4] has been efficiently implemented for the synthesis of pyrazole derivatives using various substituted enaminones, hydrazine hydrate and phenyl hydrazine under solvent-free conditions. Structural novelty and task efficiency of the catalyst, high yields of desired products, greener approach attributing high atom economy and solvent-free conditions render this protocol suitable to cope with the current demand in contemporary organic chemistry. The inventive idea of utilizing crown ether functionalized ionic liquid as a catalyst was for the first time demonstrated in this protocol.
General method for functionalized polyaryl synthesis via aryne intermediates
Truong, Thanh,Mesgar, Milad,Le, Ky Khac Anh,Daugulis, Olafs
supporting information, p. 8568 - 8576 (2014/07/07)
A method for base-promoted arylation of arenes and heterocycles by aryl halides and aryl triflates is described. Additionally, in situ electrophilic trapping of ArLi intermediates generated in the reaction of benzyne with deprotonated arenes or heterocycles has been developed, providing rapid and easy access to a wide range of highly functionalized polyaryls. Base-promoted arylation methodology complements transition-metal-catalyzed direct arylation and allows access to structures that are not easily accessible via other direct arylation methods. The reactions are highly functional-group tolerant, with alkene, ether, dimethylamino, trifluoromethyl, ester, cyano, halide, hydroxyl, and silyl functionalities compatible with reaction conditions.
I2-mediated oxidative C-N bond formation for metal-free one-pot synthesis of di-, tri-, and tetrasubstituted pyrazoles from α,β-unsaturated aldehydes/ketones and hydrazines
Zhang, Xinting,Kang, Jinfeng,Niu, Pengfei,Wu, Jie,Yu, Wenquan,Chang, Junbiao
, p. 10170 - 10178 (2015/02/19)
An I2-mediated metal-free oxidative C-N bond formation methodology has been established for the regioselective pyrazole synthesis. This practical and eco-friendly one-pot protocol requires no isolation of the less stable intermediates hydrazone
One-pot oxidation and rearrangement of propargylamines and in situ pyrazole synthesis
Chen, Jinshan,Properzi, Roberta,Uccello, Daniel P.,Young, Jennifer A.,Dushin, Russell G.,Starr, Jeremy T.
, p. 4146 - 4149 (2014/09/29)
Reported here are procedures for a one-pot oxidation and rearrangement of propargylamines to synthesize enaminones, with supporting mechanistic studies. Also reported are the extended one-pot syntheses of pyrazoles, including celecoxib and various heterocyclic compounds.
