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Search for "mechanochemistry" in Full Text gives 65 result(s) in Beilstein Journal of Organic Chemistry.
Dissecting Mechanochemistry III
Beilstein J. Org. Chem. 2022, 18, 1454–1456, doi:10.3762/bjoc.18.150
- chemical synthesis [1][2]. Within this period, the Beilstein Journal of Organic Chemistry has organized two Thematic Issues (i.e., Mechanochemistry and Mechanochemistry II) to facilitate the open dissemination of the best research in the field of synthetic organic mechanochemistry. The great success of
- these past initiatives encouraged us to organize Mechanochemistry III, a new Thematic Issue in which the readership of the journal will find a collection of full research papers, letters and, for the first time, a Perspective article. In more detail, the readers will find new mechanochemical protocols
- (Scheme 1b). Similarly, in the absence of metal catalysts, N-fluorobenzenesulfonimide (NFSI) was found to act as a mild fluorinating reagent for activated aromatics by mechanochemistry [5]. Such a collective effort to access halogenated substrates is understandable, owning the synthetic value of organic
Mechanochemical synthesis of unsymmetrical salens for the preparation of Co–salen complexes and their evaluation as catalysts for the synthesis of α-aryloxy alcohols via asymmetric phenolic kinetic resolution of terminal epoxides
Beilstein J. Org. Chem. 2022, 18, 1416–1423, doi:10.3762/bjoc.18.147
- ; mechanochemistry; phenolic KR; Introduction In the past decade, more than twenty chiral small molecule drugs were approved by the FDA, including ruxolitinib, afatinib, sonidegib, encorafenib, lorlatinib, darolutamide, alpelisib, artesunate, maribavir, ponesimod, daridorexant and others [1][2][3]. The
Polymer and small molecule mechanochemistry: closer than ever
Beilstein J. Org. Chem. 2022, 18, 1225–1235, doi:10.3762/bjoc.18.128
- (mechanochemistry) can be accomplished through various experimental strategies. Among them, ultrasonication of polymeric matrices and ball milling of reaction partners have become the two leading approaches to carry out polymer and small molecule mechanochemistry, respectively. Often, the methodological differences
- between these practical strategies seem to have created two seemingly distinct lines of thought within the field of mechanochemistry. However, in this Perspective article, the reader will encounter a series of studies in which some aspects believed to be inherently related to either polymer or small
- molecule mechanochemistry sometimes overlap, evidencing the connection between both approaches. Keywords: ball milling; mechanochemistry; mechanophore; polymer; pulsed ultrasonication; Introduction In the past two decades, the growth in popularity of mechanochemistry has been unmistakable. During this
From amines to (form)amides: a simple and successful mechanochemical approach
Beilstein J. Org. Chem. 2022, 18, 1210–1216, doi:10.3762/bjoc.18.126
- mechanochemical conditions are presented. The two methodologies exhibit complementary features as they enable the derivatization of aliphatic and aromatic amines. Keywords: acetamides; formamides; mechanochemistry; N-formylation; p-tosylimidazole; Introduction The preparation of N-formylated and N-acetylated
- substantial excess of formyl or acyl sources, often used as a solvent. Mechanochemistry has been established as a powerful tool for the rapid, clean, and environmentally friendly synthesis of organic compounds, avoiding bulk solvent and restrictions of solvent-based chemistry [27][28][29][30][31][32][33][34
- ]. In general, mechanochemistry refers to studying solid-state chemical changes promoted by external mechanical energy, such as grinding or milling. A deeper understanding of its mechanistic aspects laid the basis for further growth in this topic, opening new routes to more efficient mechanochemical
Mechanochemical bottom-up synthesis of phosphorus-linked, heptazine-based carbon nitrides using sodium phosphide
Beilstein J. Org. Chem. 2022, 18, 1203–1209, doi:10.3762/bjoc.18.125
- -PCN300) show a reduction in photoluminescent recombination, as well as a nearly two-time increase in photocurrent under broad spectrum irradiation, which are appealing properties for photocatalysis. Keywords: carbon nitride; density functional theory; mechanochemistry; phosphorus; photochemistry
- , examples of carbon nitride materials linked together via phosphorus atoms are limited, likely due to challenges in controlling the insertion of phosphorus atoms as linkers under high energy conditions. Mechanochemistry [9][10][11][12] has proven to be effective for the synthesis of a variety of polymers
- explored herein the use of solvent-free, room temperature mechanochemistry to access phosphorus-linked carbon nitride with repeating heptazine units, which were found to show improved photochemistry over pristine graphitic carbon nitride (g-CN). Additionally, the effect of a 1-hour annealing period at 300
Automated grindstone chemistry: a simple and facile way for PEG-assisted stoichiometry-controlled halogenation of phenols and anilines using N-halosuccinimides
Beilstein J. Org. Chem. 2022, 18, 999–1008, doi:10.3762/bjoc.18.100
- reaction time, and mild reaction conditions are a few noticeable merits of this environmentally sustainable mechanochemical protocol. Keywords: automated grinding; chemoselectivity; mechanochemistry; N-bromosuccinimide; PEG-400; regioselectivity; stoichiometry-controlled halogenation; Introduction Aryl
- reactivity and availability of multiple sites for substitution, often leads to an inseparable mixture of halogenated products [27][28]. Thus, a cheaper and sustainable method for a regioselective halogenation in a controlled manner is a worthy pursuit. In recent times, mechanochemistry [45][46], achieved by
- of mechanochemistry, Toda et al.’s “grindstone chemistry” [48] has also been proved as a useful technique for various organic transformations [49]. It is generally carried out by hand-grinding which is not only a labor-intensive process but also raises some concerns on the reaction kinetics
Palladium-catalyzed solid-state borylation of aryl halides using mechanochemistry
Beilstein J. Org. Chem. 2022, 18, 855–862, doi:10.3762/bjoc.18.86
- mill; borylation; cross-coupling; mechanochemistry; solid-state reaction; Introduction Arylboronic acid and its derivatives are indispensable reagents in modern synthetic chemistry because they have been frequently used for the preparation of many bioactive molecules, natural products, and functional
- substrates for the synthesis of new arylboronates that are difficult to prepare by other means is currently under investigation. Development of the first solid-state palladium-catalyzed borylation protocol of aryl halides using mechanochemistry. Substrate scope of solid aryl bromides. Reaction conditions: a
Complementarity of solution and solid state mechanochemical reaction conditions demonstrated by 1,2-debromination of tricyclic imides
Beilstein J. Org. Chem. 2022, 18, 746–753, doi:10.3762/bjoc.18.75
- ; cycloaddition; debromination; Diels−Alder reaction; mechanochemistry; Introduction The complementarity of reaction conditions [1][2][3] where the reaction takes place under some, but not under other conditions, or where a chemical reaction proceeds in a different way or mechanism is a useful feature in
- synthetic organic chemistry. Advantageously, more difficult substrates or limitations of the conditions can be overcome by the change of the reaction methods. One of the emerging synthetic methods is mechanochemistry [4][5][6][7], a greener alternative to carry out synthesis which complements heating
A trustworthy mechanochemical route to isocyanides
Beilstein J. Org. Chem. 2022, 18, 732–737, doi:10.3762/bjoc.18.73
- straightforward procedure. Keywords: green chemistry; isocyanide; isonitriles; mechanochemistry; Introduction Isocyanides were first discovered more than a century ago by Lieke in Göttingen after having handled allyl iodide and potassium cyanide to synthesize crotonic acid. This attempt, instead, brought to the
Mechanochemical halogenation of unsymmetrically substituted azobenzenes
Beilstein J. Org. Chem. 2022, 18, 680–687, doi:10.3762/bjoc.18.69
- reaction dynamics and characterization of the products was achieved by in situ Raman and ex situ NMR spectroscopy and PXRD analysis. A strong influence of the different 4,4’-substituents of azobenzene on the halogenation time and mechanism was found. Keywords: azo compounds; halogenation; mechanochemistry
DDQ in mechanochemical C–N coupling reactions
Beilstein J. Org. Chem. 2022, 18, 639–646, doi:10.3762/bjoc.18.64
- . Keywords: ball mill; 1H-benzo[d]imidazole; C(sp2)–H amidation; DDQ; mechanochemistry; quinazolin-4(3H)-one; Introduction The reawakening approaches to use solvent-free and environmentally benign conditions in organic synthesis have facilitated new opportunities [1][2][3][4]. The research area of
- mechanochemistry [5][6] mainly focuses on conducting synthetic transformations in solid-state or solvent-free conditions. Mechanochemistry is one of the emerging avenues in chemistry that can make the world more sustainable by following the “Twelve Principles of Green Chemistry” [2]. Mechanochemistry is one of the
Multi-faceted reactivity of N-fluorobenzenesulfonimide (NFSI) under mechanochemical conditions: fluorination, fluorodemethylation, sulfonylation, and amidation reactions
Beilstein J. Org. Chem. 2022, 18, 182–189, doi:10.3762/bjoc.18.20
- techniques, in this work we studied the reactivity of N-fluorobenzenesulfonimide (NFSI) by ball milling. We corroborated that, by mechanochemistry, NFSI can engage in a variety of reactions such as fluorinations, fluorodemethylations, sulfonylations, and amidations. In comparison to the protocols reported in
- solution, the mechanochemical reactions were accomplished in the absence of solvents, in short reaction times, and in yields comparable to or higher than their solvent-based counterparts. Keywords: amidation; ball mill; fluorination; in situ monitoring; mechanochemistry; NFSI; Raman monitoring
- reagent [9][10][11], and phenylsulfonyl group transfer reagent [12][13]. In the field of mechanochemistry, the usefulness of N-fluorobenzenesulfonimide has been exemplified in the asymmetric fluorination of β-keto esters (Scheme 1a) [14], and in diastereoselective fluorinations (Scheme 1b) [15], which
N-Sulfinylpyrrolidine-containing ureas and thioureas as bifunctional organocatalysts
Beilstein J. Org. Chem. 2021, 17, 2629–2641, doi:10.3762/bjoc.17.176
- organocatalysis can benefit and accommodate many sustainability techniques [29]. Mechanochemistry can increase the sustainability profile of a chemical process by reducing potentially harmful organic solvents and bring other benefits such as substantially shortened reaction times. A handful of asymmetric
The B & B approach: Ball-milling conjugation of dextran with phenylboronic acid (PBA)-functionalized BODIPY
Beilstein J. Org. Chem. 2020, 16, 2272–2281, doi:10.3762/bjoc.16.188
- , Poland 10.3762/bjoc.16.188 Abstract Mechanochemistry is an emerging and reliable alternative to conventional solution (batch) synthesis of complex molecules under green and solvent-free conditions. In this regard, we report here on the conjugation of a dextran polysaccharide with a fluorescent probe, a
- biocompatibility while remaining fluorescent. Keywords: ball milling; boronic ester; dextran; bodipy; nanoparticles; Introduction In the last few decades, mechanochemistry has gathered a great deal of attention and a lot of efforts have been focused on its use in organic synthesis, catalysis, biotransformation
- -free conditions, e.g., liquid-assisted grinding (LAG), slurries, and homogenous solutions. Although there are compounds that can only be achieved by conventional solution-based methods, mechanochemistry offers some important advantages over conventional bulk synthesis. These advantages have become more
Mechanochemical green synthesis of hyper-crosslinked cyclodextrin polymers
Beilstein J. Org. Chem. 2020, 16, 1554–1563, doi:10.3762/bjoc.16.127
- aprotic liquids (e.g., N,N-dimethylformamide or dimethyl sulfoxide), which affect the final result, especially for potential biomedical applications. This article describes a new, green synthetic pathway through mechanochemistry, in particular via ball milling and using 1,1-carbonyldiimidazole as the
- , and rhodamine B) and the still reactive imidazoyl carbonyl group of the NS. Keywords: β-cyclodextrin; ball-milling; crosslinking; green chemistry; mechanochemistry; nanosponges; Introduction The research in the fields of nanomedicine and nanotechnology has nowadays become predominant
- derivatives and are biodegradable, so they are a very promising material from this point of view. In this article a new, green synthesis of nanosponges through a mechanochemical approach is proposed. Mechanochemistry relies on the application of mechanical forces (such as compression, shear, or friction) to
Halide metathesis in overdrive: mechanochemical synthesis of a heterometallic group 1 allyl complex
Beilstein J. Org. Chem. 2019, 15, 1856–1863, doi:10.3762/bjoc.15.181
- ]∞, enable an otherwise unfavorable halide metathesis to proceed with mechanochemical assistance. From this result, we demonstrate that ball milling and unexpected solid-state effects can permit seemingly unfavored reactions to occur. Keywords: caesium; entropy; intermolecular forces; mechanochemistry
- between M'X and MX becomes particularly small? Here we describe the application of mechanochemistry in an organometallic context to examine alkali metal halide exchange unassisted by solvents. The organic group used is the bulky 1,3-bis(trimethylsilyl)allyl anion, [1,3-(SiMe3)2C3H3]− ([A']−) [13][14], for
Metal-free mechanochemical oxidations in Ertalyte® jars
Beilstein J. Org. Chem. 2019, 15, 1786–1794, doi:10.3762/bjoc.15.172
- a mechanochemical process. Keywords: AZADO; Ertalyte®; green chemistry; mechanochemistry; NaOCl·5H2O; selective oxidation; TEMPO; Introduction The conversion of primary and secondary alcohols to the corresponding carbonyl compounds (aldehydes and ketones, respectively) is of such importance in
- , especially in redox processes conducted in no-metal reactors, could prevent excessive heating of the jar, avoid the decomposition of starting materials and therefore, limit the formation of byproducts [40]. Following our interest in mechanochemistry and the design of new cost-effective oxidation procedures
- the previously described shortcomings. As of 2013, this reagent is commercially available [63], inexpensive and sufficiently stable and safe for potential applications in mechanochemistry (Figure S1a, Supporting Information File 1) [64][65][66][67]. Once the most promising oxidant was identified
Mechanochemistry II
Beilstein J. Org. Chem. 2019, 15, 1521–1522, doi:10.3762/bjoc.15.154
- Jose G. Hernandez Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, D-52074 Aachen, Germany 10.3762/bjoc.15.154 Keywords: green chemistry; mechanochemistry; methods; organic chemistry; Since the publication of the first thematic issue on mechanochemistry in the Beilstein
- Journal of Organic Chemistry in 2017 [1], the global interest in the field of mechanochemistry has continued exponentially growing. Thus, leading to the implementation of mechanochemical techniques across different areas of science. Such tremendous growth has established mechanochemistry as a sustainable
- strategy for the future of chemical synthesis. In fact, the potential of mechanochemistry in various domains of research, industry and in commercial entities has been recently recognized by the IUPAC after the inclusion of mechanochemistry among the ten chemical innovations that will change our world [2
Reaction of oxiranes with cyclodextrins under high-energy ball-milling conditions
Beilstein J. Org. Chem. 2019, 15, 1448–1459, doi:10.3762/bjoc.15.145
- have different complexation properties to those of their classically prepared analogues. Keywords: crosslinked cyclodextrin polymers; (2-hydroxy)propylcyclodextrin; mechanochemistry; nucleophile reaction; planetary ball mill; solventless synthesis; Introduction The derivatisation of natural
- factors, but also by the lack of uniformity and the site-by-site variability of prepared CDPs, which have hampered the extensive CDP use. Mechanochemistry has proven to be a useful green tool in the hands of synthetic chemists [25][26][27][28]. The reaction of epoxides with cyclodextrins under green and
Mechanochemical Friedel–Crafts acylations
Beilstein J. Org. Chem. 2019, 15, 1313–1320, doi:10.3762/bjoc.15.130
- studied by in situ Raman and ex situ IR spectroscopy. Keywords: ball milling; Friedel–Crafts reaction; mechanochemistry; Introduction The Friedel–Crafts reaction (FCR) is a very powerful tool in organic chemistry for the synthesis of aromatic ketones. It is of great industrial importance and widely used
Understanding the unexpected effect of frequency on the kinetics of a covalent reaction under ball-milling conditions
Beilstein J. Org. Chem. 2019, 15, 1226–1235, doi:10.3762/bjoc.15.120
- grinding; grinding frequency; kinetics; mechanism; mechanochemistry; Introduction We describe here an unusual frequency-dependence in the induction period of a covalent reaction carried out using ball-mill grinding. We present a kinetic analysis indicating that this is due to the successive fracture of
- crystals into smaller particles followed by the accumulation of energy in crystal defects. In recent years, manual and ball-mill grinding have become increasingly routine solid-state synthesis tools [1]. Generally referred to as mechanochemistry, these methods are more environmentally friendly and usually
- induce covalent bond formation, conducted by mechanochemistry [46]. A large induction period can be explained by two mechanisms: (1) time required for mass transport (mixing), or (2) time required for the accumulation of energy. While mass transport surely plays some role in the observed induction period
Mechanochemical amorphization of chitin: impact of apparatus material on performance and contamination
Beilstein J. Org. Chem. 2019, 15, 1217–1225, doi:10.3762/bjoc.15.119
- : amorphization; biomass; chitin; hardness; mechanochemistry; metal contamination; Introduction The last decade has seen a tremendous development in the field of mechanochemistry, which was notably covered in the New York Times in 2016 [1]. Yet, mechanochemistry is hardly a novel concept, since it is likely
- siliceous rock against pyrite [2][3]. Mechanochemistry comes with intrinsic advantages associated with the lack of solvent use during reaction, thus largely reducing the generation of waste [4] even in active pharmaceutical ingredient synthesis [5]. Yet mechanochemistry also allows the production of novel
- , with the specific reaction kinetic parameters [33]. There is, however, an interest in investigating these aspects further. In particular, it would be interesting to track the role of parameters such as ball size and mass on the progress of the reaction. In mechanochemistry, it is accepted that chemical
Mechanochemical synthesis of hyper-crosslinked polymers: influences on their pore structure and adsorption behaviour for organic vapors
Beilstein J. Org. Chem. 2019, 15, 1154–1161, doi:10.3762/bjoc.15.112
- sorption experiments with benzene and cyclohexane. Keywords: hyper-crosslinked polymers; mechanochemistry; microporous; solvent-free; vapor sorption; Introduction The widespread use of microporous materials in areas like gas storage, gas separation, and catalysis has led to the development of a wide
- recent past it has been shown that for reactions, where the solubility of the reactants or products is an issue, mechanochemistry – a field which is currently gaining momentum – can be a promising workaround [12][13][14][15][16][17][18][19][20]. It has already been established as a versatile tool for the
- synthesis of several porous materials [21][22][23][24][25][26][27][28][29] and polymers [30][31][32][33][34][35][36][37][38][39][40][41][42]. In this contribution, we employed mechanochemistry for a protocol for the solvent-free crosslinking of HCP (Figure 1). This is supported by an investigation of
Extending mechanochemical porphyrin synthesis to bulkier aromatics: tetramesitylporphyrin
Beilstein J. Org. Chem. 2019, 15, 1149–1153, doi:10.3762/bjoc.15.111
- -positions have been historically difficult in porphyrin synthesis, presumably owing to steric hindrance around the reactive site. We have used mechanochemistry for the simple, room-temperature synthesis of tetra-meso-substituted porphyrins. In the present study, mesitaldehyde undergoes acid-catalyzed
- methods. Yields of the mechanochemical synthesis were found to increase slightly upon longer exposure to an organic oxidizing agent in solution. This indicates that the mechanochemical condensation step may be more successful than initially realized. This work shows that mechanochemistry is a successful
- , simple, room-temperature method for producing tetra-meso-substituted porphyrins with bulky substituents. Keywords: condensation; grinding; mechanochemistry; milling; porphyrin; sterically-hindered; Introduction Porphyrins and related macrocycles such as chlorins, corroles, and bacteriochlorins carry
Unexpected polymorphism during a catalyzed mechanochemical Knoevenagel condensation
Beilstein J. Org. Chem. 2019, 15, 1141–1148, doi:10.3762/bjoc.15.110
- monitoring multi-phase reactions during ball milling. Keywords: ball milling; C–C coupling; in situ; mechanochemistry; multivariate data analysis; Introduction Mechanochemistry offers a wide array of applications. It is used widely for synthesis of inorganic, metal-organic, and organic molecules and
- materials [1]. Interest in these methods stems largely from the fact that they are efficient and more environmentally friendly as compared to traditional approaches [2][3]. Mechanochemistry is a well-established method for the synthesis of coordination polymers, the formation of cocrystals, and in C–C
- coupling reactions [4][5][6][7]. Despite the increasing use of mechanochemistry, there is still a lack in understanding of the underlying processes involved during mechanically-facilitated reactions. This is particularly true of the potential role of transient polymorphic phases [8] and seeding effects [9
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