63637-59-2Relevant academic research and scientific papers
Solvent-dependent copper-catalyzed synthesis of pyrazoles under aerobic conditions
Pünner, Florian,Sohtome, Yoshihiro,Sodeoka, Mikiko
, p. 14093 - 14096 (2016/12/09)
We present a copper-catalyzed oxidative cyclization of β,γ-unsaturated hydrazones, utilizing molecular oxygen as a stoichiometric oxidant. The methodology provides distinct classes of pyrazoles simply by changing the reaction solvent. Tris-substituted pyr
Cu-promoted sydnone cycloadditions of alkynes: Scope and mechanism studies
Comas-Barcel?3, Jffllia,Foster, Robert S.,Fiser, B??la,Gomez-Bengoa, Enrique,Harrity, Joseph P. A.
, p. 3257 - 3263 (2015/03/05)
Cu salts have been found to promote the cycloaddition reaction of sydnones and terminal alkynes, providing significant reduction in reaction times. Specifically, the use of Cu(OTf)2 is found to provide 1,3-disubstituted pyrazoles, whereas simpl
An efficient regioselective copper catalyzed multi-component synthesis of 1,3-disubstituted pyrazoles
Raghunadh, Akula,Meruva, Suresh Babu,Mekala, Ramamohan,Raghavendra Rao,Krishna, Thalishetti,Gangadhara Chary,Vaikunta Rao,Syam Kumar
, p. 2986 - 2990 (2014/05/06)
An efficient synthesis of unsymmetrically substituted 1,3-pyrazole derivatives has been developed via three-component coupling reaction involving 3-(dimethylamino)-1-phenylprop-2-en-1-one, hydrazine, and aryl halides in one pot process exhibiting high regioselectivity. The pyrazole synthesis proceeds via a sequential series of reactions such as Michael addition, heterocyclization, dehydration, and Ullmann cross-coupling.
Practical synthesis of pyrazoles via a copper-catalyzed relay oxidation strategy
Tang, Xiaodong,Huang, Liangbin,Yang, Jidan,Xu, Yanli,Wu, Wanqing,Jiang, Huanfeng
supporting information, p. 14793 - 14796 (2014/12/11)
Various 1,3- and 1,3,4-substituted pyrazoles are smoothly formed via copper-catalyzed cascade reactions of oxime acetates, amines and aldehydes. This relay oxidative process involves copper-promoted N-O bond cleavage and C-C/C-N/N-N bond formations to furnish pyrazolines, and sequential Cu-O2 system-involved oxidative dehydrogenation of pyrazolines to afford pyrazoles. This transformation provides a novel and versatile approach for the synthesis of pyrazoles, with an inexpensive copper catalyst and green oxidants. It is atom- and step-economical, and possesses a good functional group tolerance, as well as operational simplicity. This journal is
Palladium-catalyzed dehalogenation of 5-halopyrazoles
Chen, Chun-Yen,Huang, Yu-Ying,Su, Wei-Nien,Kaneko, Kimiyoshi,Kimura, Masayuki,Takayama, Hiroyuki,Wong, Fung Fuh
, p. 183 - 189 (2012/05/05)
A new and efficient method for the dehalogenation of 5-halopyrazoles was developed by using the catalytic amount of palladium (II) chloride and triphenylphosphine as a ligand at reflux under constant flow of hydrogen gas. The reaction gave the correspondi
Alkyne [3 + 2] cycloadditions of iodosydnones toward functionalized 1,3,5-trisubstituted pyrazoles
Browne, Duncan L.,Taylor, John B.,Plant, Andrew,Harrity, Joseph P. A.
supporting information; experimental part, p. 984 - 987 (2010/05/18)
(Chemical Equation Presented) The cycloaddition of 4-iodosydnones with terminal alkynes proceeds with excellent regiocontrol to provide 5-iodo pyrazoles. These products participate smoothly in subsequent C-C and C-heteroatom bond forming processes.
