Recent Advances in the Synthesis of Pyrazole Derivatives: A Review

Reactions, Journal Year: 2023, Volume and Issue: 4(3), P. 478 - 504

Published: Sept. 5, 2023

Pyrazole, characterized by a five-membered heterocyclic structure featuring two neighboring nitrogen atoms, serves as core element. Pyrazoles hold privileged status versatile frameworks in various sectors of the chemical industry, including medicine and agriculture. Previous reviews have extensively highlighted significance pyrazoles their diverse biological activities, encompassing roles such antituberculosis, antimicrobial, antifungal, anti-inflammatory, anticancer, antidiabetic agents. Consequently, they garnered substantial interest from researchers. The aim this review is to offer comprehensive overview published research related synthesis pyrazole derivatives, discussion methods for accessing moiety. These span utilizing transition-metal catalysts photoredox reactions employing one-pot multicomponent processes, novel reactants, innovative reaction types. It encompasses studies conducted numerous scientists worldwide, showcasing collective efforts advancing methodologies applications derivatives.

Language: Английский

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DMSO as a C₁ Source for [2 + 2 + 1] Pyrazole Ring Construction via Metal-Free Annulation with Enaminones and Hydrazines

Organic Letters, Journal Year: 2021, Volume and Issue: 24(1), P. 228 - 233

Published: Dec. 15, 2021

A cascade reaction between enaminones, hydrazines, and dimethyl sulfoxide (DMSO) for the synthesis of 1,4-disubstituted pyrazoles catalyzed by molecular iodine in presence Selectfluor has been realized. DMSO plays a dual role as C1 source medium. In addition, 1,3,4-trisubstituted using aldehydes alternative building blocks also achieved.

Language: Английский

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Synthetic and biosynthetic routes to nitrogen–nitrogen bonds

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(8), P. 2991 - 3046

Published: Jan. 1, 2022

The nitrogen–nitrogen bond is a core feature of diverse functional groups like hydrazines, nitrosamines, diazos, and pyrazoles.

Language: Английский

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2H‐Azirines: Recent Progress in Synthesis and Applications

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 27(11)

Published: Jan. 29, 2024

Abstract 2H ‐arizines are important three‐membered heterocycles in organic chemistry. Recently, many advances the synthesis and functionalization of have been reported. Neber rearrangement, isomerization isoxazole, oxidation enamine, C−H bond activation, decomposition vinyl azide, alkyne, multi‐step developed for efficient assembly ‐azirines. As versatile highly strained unsaturated heterocycles, ‐azirines can be used as distinctive building blocks towards significant functional groups, attracted extensive attention fabrication numerous heterocycles. Recent studies focused on [3+n] ring‐expansion reactions, nucleophilic addition C=N double or continuous followed by cyclization, ring‐opening to acyclic compounds, substitution sp 3 ‐C−H One most critical challenges is seeking a selective opening specific three bonds azirine circle, some what achieved basis metal catalyst, photocatalysis, combination catalyst photocatalysis. In this review, recent involving reactivity accompanied with breakthroughs summarized. The review mainly covers period from 2019 2023.

Language: Английский

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In situ generation and conversion of a half-zirconocene catalyst for the synthesis of N-acylpyrazoles

RSC Advances, Journal Year: 2025, Volume and Issue: 15(3), P. 1747 - 1753

Published: Jan. 1, 2025

A catalytic system for the in situ formation of a half-zirconocene catalyst under mild conditions N -acylpyrazoles synthesis.

Language: Английский

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Pyrazole Scaffold Synthesis, Functionalization, and Applications in Alzheimer’s Disease and Parkinson’s Disease Treatment (2011–2020)

Molecules, Journal Year: 2021, Volume and Issue: 26(5), P. 1202 - 1202

Published: Feb. 24, 2021

The remarkable prevalence of pyrazole scaffolds in a versatile array bioactive molecules ranging from apixaban, an anticoagulant used to treat and prevent blood clots stroke, bixafen, pyrazole-carboxamide fungicide control diseases rapeseed cereal plants, has encouraged both medicinal organic chemists explore new methods developing pyrazole-containing compounds for different applications. Although numerous synthetic strategies have been developed the last 10 years, there not comprehensive overview synthesis implication recent advances treating neurodegenerative disease. This review first presents scaffold their functionalization that published during decade (2011–2020). We then narrow focus application these development therapeutics diseases, particularly Alzheimer’s disease (AD) Parkinson’s (PD).

Language: Английский

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P^III/P^V═O-Catalyzed Intermolecular N–N Bond Formation: Cross-Selective Reductive Coupling of Nitroarenes and Anilines

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(36), P. 14464 - 14469

Published: Sept. 2, 2021

An organophosphorus-catalyzed method for the synthesis of unsymmetrical hydrazines by cross-selective intermolecular N-N reductive coupling is reported. This employs a small ring phosphacycle (phosphetane) catalyst together with hydrosilane as terminal reductant to drive nitroarenes and anilines good chemoselectivity functional group tolerance. Mechanistic investigations support an autotandem catalytic reaction cascade in which organophosphorus drives two sequential mechanistically distinct reduction events via PIII/PV═O cycling order furnish target bond.

Language: Английский

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Hydroxyl-Directed Rh(III)-Catalyzed C–H Functionalization: Access to Benzo[de]chromenes

Organic Letters, Journal Year: 2023, Volume and Issue: 25(10), P. 1622 - 1627

Published: March 3, 2023

A cascade oxidative annulation reaction of heterocyclic ketene aminals (HKAs) with internal alkynes catalyzed by [Cp*RhCl2]2 and oxidized Cu(OAc)2·H2O was developed to efficiently synthesize highly functionalized benzo[de]chromene derivatives in good excellent yields. The proceeded the sequential cleavage C(sp2)-H/O-H C(sp2)-H/C(sp2)-H bonds. These multicomponent reactions were regioselective. In addition, all products exhibited intense fluorescence emission solid state, they demonstrated concentration-dependent quenching presence Fe3+, indicating that these compounds could be used recognition Fe3+.

Language: Английский

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Recent advances in multicomponent synthesis of pyrazoles

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

Pyrazole moiety is considered as an important N-heterocycle in pharmaceuticals and many other functional molecules. The utilization of multicomponent reaction a major tool the current approaches pyrazole synthesis. Considering power significance synthesis, we review herein latest developments this field. According to typical features, contents are divided into reactions with different NN fragment sources, such hydrazine, hydrazone, amidine, nitrile, diazo compounds, ring construction, covering works published since 2019 date.

Language: Английский

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Copper-Promoted Aerobic Oxidative [3+2] Cycloaddition Reactions of N,N-Disubstituted Hydrazines with Alkynoates: Access to Substituted Pyrazoles

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(4), P. 2190 - 2206

Published: Feb. 1, 2023

A copper-promoted aerobic oxidative [3+2] cycloaddition reaction for the synthesis of various substituted pyrazoles from N,N-disubstituted hydrazines with alkynoates in presence bases is developed. This work involves a direct C(sp3)-H functionalization and formation new C-C/C-N bonds. In this strategy, inexpensive easily available Cu2O serves as promoter air acts green oxidant. The exhibits advantages high atom step economy, regioselectivity, easy operation.

Language: Английский

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