Salient Achievements in Synthetic Organic Chemistry Enabled by Mechanochemical Activation

Synthesis, Год журнала: 2023, Номер 55(16), С. 2439 - 2459

Опубликована: Май 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

Язык: Английский

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Intermediates in Mechanochemical Reactions

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(14)

Опубликована: Янв. 5, 2024

Abstract Mechanochemical reactions offer methodological and environmental advantages for chemical synthesis, constantly attracting attention within the scientific community. Besides unmistakable sustainability advantages, conditions under which mechanochemical occur, namely solventless conditions, sometimes facilitate isolation of otherwise labile or inaccessible products. Despite these limited knowledge exists regarding mechanisms types intermediates involved. Nevertheless, in an expanding number cases, ex situ monitoring techniques have allowed observation, characterization, reaction transformations. In this Minireview, we present a series examples reactive been detected spanning organic, organometallic, inorganic, materials chemistry. Many were stabilized by non‐covalent interactions, played pivotal role guiding We believe that uncovering understanding such instances, growing mechanochemistry community could find novel opportunities catalysis discover new while achieving simplification design.

Язык: Английский

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Milling Medium‐Free Suzuki Coupling by Direct Mechanocatalysis: From Mixer Mills to Resonant Acoustic Mixers**

Chemistry - A European Journal, Год журнала: 2023, Номер 29(65)

Опубликована: Июль 28, 2023

Here we describe the development of a sustainable and cost-effective approach for catalytic cross-coupling reactions in mechanochemistry. It is found that substrate's impact with vessel wall alone sufficient to initiate reaction, thus indicating milling balls function primarily as mixing agent direct mechanocatalytic Suzuki coupling. The absence can be offset by adjusting rheology using liquid-assisted grinding (LAG). LAG sweet spot 0.25 μL mg-1 confirmed both resonance acoustic mixers (RAMs) ball-free mixer mills, higher than presence balls. RAMs exhibit excellent performance achieving yields 90 % after 60 min complete conversion min. longevity significantly improved RAM, allowing at least 20 without deterioration.

Язык: Английский

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Opportunities and Challenges in Applying Solid‐State NMR Spectroscopy in Organic Mechanochemistry

Advanced Materials, Год журнала: 2023, Номер 35(52)

Опубликована: Июль 5, 2023

In recent years it is shown that mechanochemical strategies can be beneficial in directed conversions of organic compounds. Finding new reactions proved difficult, and due to the lack mechanistic understanding reaction events, respective efforts have mostly remained empirical. Spectroscopic techniques are crucial shedding light on these questions. this overview, opportunities challenges solid-state nuclear magnetic resonance (NMR) spectroscopy field mechanochemistry discussed. After a brief discussion basics high-resolution NMR under magic-angle spinning (MAS) conditions, seven for presented, ranging from ex situ approaches structurally elucidated products obtained by milling potential limitations approaches. Particular strengths NMR, instance differentiating polymorphs, NMR-crystallographic structure-determination protocols, or detecting weak noncovalent interactions molecular-recognition events employing proton-detected experiments at fast MAS frequencies,

Язык: Английский

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Halogen-bonded cocrystals via resonant acoustic mixing

RSC Mechanochemistry, Год журнала: 2024, Номер 1(1), С. 50 - 62

Опубликована: Янв. 1, 2024

Resonant acoustic mixing (RAM) is shown to be an effective mechanochemical method for producing halogen-bonded cocrystals, characterized here by X-ray diffraction and solid-state NMR. An elusive stoichiomorph unobtainable milling found via RAM.

Язык: Английский

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Sustainable click reactions: Use of greener reaction media in the synthesis of 1,2,3-triazoles

Tetrahedron, Год журнала: 2024, Номер 157, С. 133964 - 133964

Опубликована: Март 31, 2024

Язык: Английский

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Synthesis of Quinazolinones and Benzothiazoles Using α-Keto Acids under Ball Milling

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(8), С. 5229 - 5238

Опубликована: Март 29, 2024

Mechanochemistry refers to the initiation of chemical reactions via mechanical forces such as milling, grinding, or shearing achieve transformations. As a manifestation mechanocatalysis, herein, an oxidant-free and solvent-free approach for synthesis quinazolinones (23 derivatives) benzothiazoles has been developed through stainless-steel-driven decarboxylative acyl radical generation from α-keto acids. A library 2-arylquinazolinones 2-arylbenzothiazoles prepared in moderate good yields at room temperature. Moreover, control experiments XPS studies supported reduction (by zerovalent iron) molecular oxygen abrasion balls, which promoted superoxide anion SET process.

Язык: Английский

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Mechanochemical aerobic oxidative Heck coupling by polymer-assisted grinding: cyclodextrin additive facilitating regioselectivity control

Green Chemistry, Год журнала: 2024, Номер 26(10), С. 5890 - 5899

Опубликована: Янв. 1, 2024

A novel approach utilizing the polymer-assisted grinding (POLAG) technique to facilitate regioselective oxidative Heck coupling of aryl boronic acids with electronically unbiased olefins under solvent-free conditions was presented.

Язык: Английский

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Shaking Up the Friedländer Reaction: Rapid, Scalable Mechanochemical Synthesis of Polyaryl‐substituted Quinolines

Advanced Synthesis & Catalysis, Год журнала: 2024, Номер unknown

Опубликована: Авг. 16, 2024

Abstract Quinolines are ubiquitous heterocyclic aromatic scaffolds, which can be found in many natural and synthetic products. They highly valued for their pharmacological electrochemical properties, encouraging the discovery of new routes quinoline synthesis diversification. In particular, polyaryl‐substituted quinolines have recently surged as useful substrates a wide variety applications, yet remain difficult inefficient. Herein, we report rapid novel mechanochemical Friedländer under basic conditions using ball milling. The optimized reaction resulted moderate to excellent yields ranging from 48% >95% demonstrated broad functional group tolerance at 1 hour times. We further show route photocatalyst DPQN 2,4−di−OMe photo‐ligand PPQN well OLED donor‐acceptor pCzPPQ, electron transport material oligoquinoline TQB organic semiconductor DPA. A gram scale was also achieved Resonant Acoustic Mixing (RAM), providing an isolated yield 87% after simple recrystallization ethanol.

Язык: Английский

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On the Physical Processes of Mechanochemically Induced Transformations in Molecular Solids

Chemical Communications, Год журнала: 2024, Номер 60(99), С. 14750 - 14761

Опубликована: Янв. 1, 2024

Initiating or sustaining physical and chemical transformations with mechanical force – mechanochemistry provides an opportunity for more sustainable processes, access to new reactivity.

Язык: Английский

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