67203-58-1Relevant academic research and scientific papers
Sunlight-promoted Direct Irradiation of N-centred Anion: The Photocatalyst-free Synthesis of Pyrazoles in Water
Zhang, Te,Meng, Yunge,Lu, Jinye,Yang, Yuting,Li, Gong-Qiang,Zhu, Chunyin
supporting information, p. 3063 - 3068 (2017/12/04)
A practical method through sunlight mediated annulation of α,β-unsaturated hydrazones has been developed for the synthesis of pyrazole. Based on the analysis of UV-Vis absorption of the substrate, the reaction was designed to avoid the use of external photocatalysis and proceeds via direct irradiation of N-centred anion by sunlight. The key features of this reaction include operational simplicity, readily available reagents, and amenability to gram-scale synthesis. (Figure presented.).
The diaza-Nazarov cyclization involving a 2,3-diaza-pentadienyl cation for the synthesis of polysubstituted pyrazoles
Aegurla, Balakrishna,Peddinti, Rama Krishna
, p. 9643 - 9652 (2017/11/30)
An unprecedented iodine-mediated diaza-Nazarov (DAN) type cyclization for the construction of substituted pyrazoles from easily available starting materials via an enamine-iminium ion intermediate is described. The oxidative cyclization worked under green conditions with remarkable regioselectivity. This one-pot, efficient and operationally simple three-component intramolecular regioselective DAN cyclization displayed a wide range of substrate scope. The dichotomy of reaction pathways has been explored with density functional theory in the gas phase and solution phase. Of the possible 1,5-, 1,6-, and 1,7-electrocyclizations, the DAN cyclization, i.e., the 1,5-pathway offers the lowest activation energy barrier supporting our experimental observations.
METABOTROPIC GLUTAMATE RECEPTOR NEGATIVE ALLOSTERIC MODULATORS (NAMS) AND USES THEREOF
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Paragraph 00373, (2016/01/01)
Provided herein are small molecule active metabotropic glutamate subtype-2 and -3 receptor negative allosteric modulators (NAMs), compositions comprising the compounds, and methods of using the compounds and compositions.
An efficient one-pot synthesis of 3,5-disubstituted 1H-pyrazoles
Wu, Lei-Lei,Ge, Yi-Cen,He, Ting,Zhang, Lei,Fu, Xing-Li,Fu, Hai-Yan,Chen, Hua,Li, Rui-Xiang
experimental part, p. 1577 - 1583 (2012/06/29)
An efficient, general, one-pot, three-component procedure for the preparation of 3,5-disubstituted 1H-pyrazoles via condensation of substituted aromatic aldehydes, tosylhydrazine and terminal alkynes in toluene is reported. The reaction tolerates a variety of functional groups and sterically hindered substrates to afford the desired pyrazoles in yields of 67-91%.
