Salient Achievements in Synthetic Organic Chemistry Enabled by Mechanochemical Activation

Synthesis, Journal Year: 2023, Volume and Issue: 55(16), P. 2439 - 2459

Published: May 3, 2023

Abstract Although known for millennia, it is only recently that mechanochemistry has received serious attention by chemists. Indeed, during the past 15 years an extraordinary number of reports concerning solid-state chemical transformations through grinding and milling techniques have been recorded. This short review discusses circumstances led this renaissance, highlighting present intense interest in so-called green chemistry, enabling capacity to handle insoluble substrates, identification profound influence additives can on mechanochemically activated reactions. The core account focuses salient developments synthetic organic especially amino acid peptide­ mechanosynthesis, successful employment mechanochemical activation combination with asymmetric organocatalysis, promising enzymatic whole cell biocatalysis, remarkable achievement multicomponent selective reactions via complex, multistep reaction pathways, mechanosynthesis representative heterocycles. final section comments some pending tasks area, such as scaling-up processes be practical use industry, requirement easier more efficient control parameters monitoring devices, consequently careful analysis additional procedures a proper understanding phenomena. 1 Introduction 2 Brief History Mechanochemistry 3 Milling Equipment Reaction Parameters 4 Attributes That Propelled Its Present Renaissance 4.1 Enormous Attention Being Presently Paid Sustainable Chemistry 4.2 Reduced Energy Consumption 4.3 Additive-Based 4.4 Handling Insoluble Reactants 4.5 ‘Impossible’ Reactions Are Successful 4.6 Air- Water-Sensitive Reagents Ball 5 Salient Developments Mechanochemical Activation Synthetic Organic 5.1 Amino Acid Peptide Mechanosynthesis 5.2 Asymmetric Synthesis Organocatalysis under Ball-Milling Conditions 5.3 Mechanoenzymology 5.4 Multicomponent Activated 5.5 Heterocycles Modification 6 Future Directions 6.1 Scaling-Up Protocols 6.2 Temperature-Controlled 6.3 Understanding Transformations 6.4 Emerging Techniques 7 Conclusions

Language: Английский

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Mechanochemical Approach for Air‐Tolerant and Extremely Fast Lithium‐Based Birch Reductions in Minutes

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(21)

Published: March 22, 2023

Birch reduction has been widely used in organic synthesis for over half a century as powerful method to dearomatize arenes into 1,4-cyclohexadiene derivatives. However, the conventional reaction using liquid ammonia requires laborious procedures ensure inert conditions and low temperatures. Although several ammonia-free modifications have reported, development of an operationally simple, efficient, scalable protocol remains challenge. Herein, we report lithium-based air without special operating ball-milling technique. This is characterized by its operational simplicity extremely short time (within 1 min), probably owing situ mechanical activation lithium metal, broad substrate scope, no requirement dry bulk solvents. The potential our flash also demonstrated efficient bioactive target molecules gram-scale synthesis.

Language: Английский

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Dynamic Li⁺ Capture through Ligand‐Chain Interaction for the Regeneration of Depleted LiFePO₄ Cathode

Advanced Materials, Journal Year: 2024, Volume and Issue: 36(14)

Published: Jan. 4, 2024

Abstract After application in electric vehicles, spent LiFePO 4 (LFP) batteries are typically decommissioned. Traditional recycling methods face economic and environmental constraints. Therefore, direct regeneration has emerged as a promising alternative. However, irreversible phase changes can significantly hinder the efficiency of process owing to structural degradation. Moreover, improper storage treatment practices lead metamorphism, further complicating process. In this study, sustainable recovery method is proposed for electrochemical repair LFP batteries. A ligand‐chain Zn‐complex (ZnDEA) utilized regulator, with its ─NH─ group alternatingly facilitating binding preferential transition metal ions (Fe 3+ during charging Zn 2+ discharging). This dynamic coordination ability helps modulate volume within recovered framework. Consequently, framework store more Li‐ions, enhance reversibility between FePO (FP), modify initial Coulombic efficiency, reduce polarization voltage differences. The cells exhibit excellent capacity retention 96.30% after 1500 cycles at 2 C. ligand chain mechanism promotes evolution facilitate ion migration, providing valuable insights into targeted compensation environmentally friendly practical applications.

Language: Английский

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Direct mechanocatalysis by resonant acoustic mixing (RAM)

Chemical Science, Journal Year: 2023, Volume and Issue: 14(27), P. 7475 - 7481

Published: Jan. 1, 2023

We demonstrate the use of a metal surface to directly catalyse copper-catalysed alkyne-azide click-coupling (CuAAC) reactions under conditions Resonant Acoustic Mixing (RAM) - recently introduced and scalable mechanochemical methodology that uniquely eliminates need for bulk solvent, as well milling media. By using simple copper coil catalyst, this work shows direct mechanocatalysis can occur in an impact-free environment, relying solely on high-speed mixing reagents against surface, without specially designed containers introducing experimental setup enables real-time Raman spectroscopy monitoring RAM processes, we 0th-order reaction kinetics several selected CuAAC reactions, supporting surface-based catalysis. The herein presented RAM-based is simple, effective one-pot, two-step synthesis triazoles

Language: Английский

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Mechanochemical synthesis of organoselenium compounds

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Jan. 26, 2024

We disclose herein a strategy for the rapid synthesis of versatile organoselenium compounds under mild conditions. In this work, magnesium-based selenium nucleophiles are formed in situ from easily available organic halides, magnesium metal, and elemental via mechanical stimulation. This process occurs liquid-assisted grinding (LAG) conditions, requires no complicated pre-activation procedures, operates broadly across diverse range aryl, heteroaryl, alkyl substrates. symmetrical diselenides efficiently obtained after work-up air, while one-pot nucleophilic addition reactions with various electrophiles allow comprehensive unsymmetrical monoselenides high functional group tolerance. Notably, method is applied to regioselective selenylation diiodoarenes polyaromatic aryl halides that difficult operate solution approaches. Besides selenium, sulfur tellurium also competent process, which showcases potential methodology facile organochalcogen compounds.

Language: Английский

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Mechanochemistry enabling highly efficient Birch reduction using sodium lumps and d-(+)-glucose

Chemical Science, Journal Year: 2024, Volume and Issue: 15(12), P. 4452 - 4457

Published: Jan. 1, 2024

In this study, a mechanochemical protocol for highly efficient and ammonia-free sodium-based Birch reduction was developed, leveraging the use of cheap easy-to-handle sodium lumps d -(+)-glucose as proton source.

Language: Английский

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Mechanochemical protocol facilitates the generation of arylmanganese nucleophiles from unactivated manganese metal

Chemical Science, Journal Year: 2022, Volume and Issue: 14(3), P. 499 - 505

Published: Nov. 28, 2022

The direct synthesis of organomanganese reagents from organic halides and manganese metal remains a challenge. Current solution-based approaches require the preparation activated (Rieke manganese) or use multiple additives to promote insertion into carbon-halogen bond. Here, we show that mechanochemical ball-milling protocol facilitates generation various arylmanganese nucleophiles aryl commercially available, unactivated without need for complicated pre-activation processes additives. These manganese-based carbon can be used directly one-pot addition reactions with electrophiles palladium-catalyzed cross-coupling under bulk-solvent-free conditions. Importantly, all experimental operations conducted atmospheric

Language: Английский

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Synthesis without solvent: consequences for mechanochemical reactivity

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(96), P. 14210 - 14222

Published: Jan. 1, 2023

Solution-based reactions are a staple of synthetic chemistry—but what happens mechanochemically, when there is no solvent?

Language: Английский

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C-4 Regioselective Alkylation of Pyridines Driven by Mechanochemically Activated Magnesium Metal

Organic Letters, Journal Year: 2023, Volume and Issue: 25(14), P. 2531 - 2536

Published: April 5, 2023

Mechanochemically activated magnesium(0) metal as a highly active mediator driving direct C-4–H alkylation of pyridines with alkyl halides has been developed. Excellent regioselectivity and substrate scope, including those containing reducible functionalities, free amines, alcohols, well biologically relevant molecules were achieved to access 4-alkylpyridine products. Preliminary mechanistic studies suggested radical–radical coupling pathway.

Language: Английский

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Mechanochemical Birch Reduction with Low Reactive Alkaline Earth Metals

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(20)

Published: March 4, 2024

Abstract Birch reduction and similar dissolved metal‐type transformations hold significant importance in the organic synthesis toolbox. Historically, field has been dominated by alkali metal reductants. In this study, we report that largely neglected, low‐reactive alkaline earth metals can become powerful affordable reductants when used a ball mill under essentially solvent‐free conditions, presence of ethylenediamine THF as liquid additives. Calcium reduce both electron‐deficient electron‐rich arenes, with yields products to those obtained lithium metal. Magnesium reveals enhanced reducing power, enabling benzoic acids while keeping aromatic moieties intact allows for chemoselective transformations. The developed mechanochemical approach uses readily available safer‐to‐handle metals, operates air ambient temperature be gram‐scale preparations. Finally, demonstrate conditions other reductive transformations, including amination, deoxygenation, dehalogenation, alkene alkyne reductions.

Language: Английский

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