Application of Fe3O4@SiO2@sulfamic acid magnetic nanoparticles as recyclable heterogeneous catalyst for the synthesis of imine and pyrazole derivatives in aqueous medium
作者:B. Zakerinasab、M. A. Nasseri、H. Hassani、M. M. Samieadel
DOI:10.1007/s11164-015-2204-1
日期:2016.4
Sulfamic acid supported on Fe3O4@SiO2 superpara magnetic nanoparticles was successfully applied as a recyclable solid acid catalyst with a large density of sulfamic acid groups for the synthesis of pyrazole derivatives, an important class of potentially bioactive compounds. The products are obtained in high yield from the one-pot reaction procedure involving dicarbonyl compounds and hydrazines/hydrazides. This new method totally avoids the use of toxic or expensive solvents and organic acids in this reaction.
Facile One-Pot Synthesis of 1,3,5-Trisubstituted Pyrazoles from α,β-Enones
作者:Jin Yu、Ko Hoon Kim、Hye Ran Moon、Jae Nyoung Kim
DOI:10.5012/bkcs.2014.35.6.1692
日期:2014.6.20
efficient one-pot synthesis of 1,3,5-trisubstituted pyrazoles from α,β-enones and arylhydrazinehydrochlorides has been developed. The pyrazoles were formed via a tandem formation of the correspondingpyrazolines and an acid-catalyzed aerobic oxidation process.Key Words : Pyrazoles, One-pot synthesis, Aerobic oxidation, α,β-Enones Introduction1,3,5-Trisubstituted pyrazolines are important heterocycliccompounds
Abstract An efficient and simple oxidative protocol has been developed for the preparation of pyrazoles from pyrazolines mediated by TBHP/Cu(OAc)2 at room temperature. The present protocol has been successfully applied for the preparation of various pyrazole compounds from heterocyclic pyrazolines.
The visible light mediated oxidation of 1,3,5-trisubstitutedpyrazolines under metal-free conditions was developed. Various substituted pyrazolines were oxidized to pyrazoles by irradiation with visible light/sunlight. A plausible mechanism was proposed for the light mediated oxidation proceeding via formation of intermediates with electron rich C-3 positions and electron deficient C-5 positions. Correlation
Intramolecular oxidative C–N bond formation under metal-free conditions: One-pot global functionalization of pyrazole ring
作者:Mohit K. Tiwari、Ashif Iqubal、Parthasarathi Das
DOI:10.1016/j.tet.2022.133059
日期:2022.11
of intermediate free-radical species followed by intramolecular oxidative C–N bondformation afforded the desired pyrazole moiety. The synthetic versatility of this methodology is further highlighted by preparing a diverse range of substrates including di-/tri-/and tetra-substituted pyrazoles, and applying the methodology in the practical synthesis of bioactive scaffolds.