Mechanochemical solid state synthesis of copper(I)/NHC complexes with K₃PO₄

• Ina Remy-Speckmann,
• Birte M. Zimmermann,
• Mahadeb Gorai,
• Martin Lerch and
• Johannes F. Teichert

Beilstein J. Org. Chem. 2023, 19, 440–447, doi:10.3762/bjoc.19.34

• preparation of copper(I)/NHC complexes [45][47]. All mechanochemical syntheses were carried out in a planetary ball mill and the vessel was loaded in an argon-filled glovebox. Copper(I) chloride, imidazolium salt 3 and the appropriate base were mixed (in a molar ratio of 1.0:1.0:1.5, respectively) and ground

• , which are difficult or wasteful to be prepared by typical liquid state synthesis methods. Experimental Mechanochemical synthesis procedure for 5: The product was synthesized using a Fritsch Pulverisette 7 classic line, a high-energy planetary ball mill. The starting materials 1-(2-(2,3-diisopropyl-1

Polymer and small molecule mechanochemistry: closer than ever

• José G. Hernández

Beilstein J. Org. Chem. 2022, 18, 1225–1235, doi:10.3762/bjoc.18.128

• influenced by tensile forces. In contrast, compressive forces in the same direction as the collision less strongly activate the chemical bonds, but the large number of this type of collisions in a planetary ball mill (Figure 1c) can add up and provide compressive forces large enough for the activation of

• the covalent capsule 5 (made from resorcinarene caps connected by four dihydrazone units of ʟ-cysteine) with C60 and C70 fullerenes upon neat ball milling in a planetary ball mill (Figure 6). The mechanochemical complexation is remarkable since the porous capsule does not possess large enough openings

• mechanochemical reactions occur. As a result, the field of mechanochemistry as a whole will ultimately be strengthened. Representation of (a) cavitation and elongational flow caused by pulsed ultrasonication, (b) mixer mill, (c) planetary ball mill, and (d) ring-and-puck mill (vibrating disc mill). Structure of

Mechanochemical green synthesis of hyper-crosslinked cyclodextrin polymers

• Alberto Rubin Pedrazzo,
• Fabrizio Caldera,
• Marco Zanetti,
• Silvia Lucia Appleton,
• Nilesh Kumar Dhakar and
• Francesco Trotta

Beilstein J. Org. Chem. 2020, 16, 1554–1563, doi:10.3762/bjoc.16.127

• modifications of starch using ball milling have been reported. These included esterifications and etherifications of starch [19] and cellulose [20]. In 2017, Jicsinszky et al. obtained CD derivatives through a solid-state reaction, using a planetary ball mill [21][22] and by other green processes [23]. The main

• . The cyclodextrins were dried before use in an oven at 100 °C until constant weight. Elemental analyses were performed on a Thermo Scientific FlashEA 1112, using vanadium pentoxide purchased from Sigma. As planetary ball mill, a Retsch PM200 High Speed Planetary Ball Mill was used, with 20 sintered

Reaction of oxiranes with cyclodextrins under high-energy ball-milling conditions

• László Jicsinszky,
• Federica Calsolaro,
• Katia Martina,
• Fabio Bucciol,
• Maela Manzoli and
• Giancarlo Cravotto

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

• solventless conditions is discussed in this report. The HEBM technique was performed in a planetary ball mill for this purpose [12][29]. Proof of concept and reagent use were investigated for the most common HPCDs. Substitution patterns were not the target of our study as the modification of current

• purification, except the ion-exchangers. The ion-exchangers were freshly washed with water and methanol until the washing solutions became colourless and UV inactive. Reactions were carried out in a planetary ball mill (Retsch PM100 High Speed Planetary Ball Mill), using a 50 mL stainless steel jar and mix of

Mechanochemical synthesis of hyper-crosslinked polymers: influences on their pore structure and adsorption behaviour for organic vapors

• Sven Grätz,
• Sebastian Zink,
• Hanna Kraffczyk,
• Marcus Rose and
• Lars Borchardt

Beilstein J. Org. Chem. 2019, 15, 1154–1161, doi:10.3762/bjoc.15.112

• physisorption experiments, all samples were activated at 353 K for 24 h under vacuum. Ball mill syntheses were carried out in a Fritsch Pulverisette 7 premium line planetary ball mill. Infrared spectroscopy (IR) was carried out on a Bruker Vertex 70 with a Specac Golden Gate ATR unit. A resolution of 2 cm−1 was

Synthesis of acylglycerol derivatives by mechanochemistry

• Karen J. Ardila-Fierro,
• Andrij Pich,
• Marc Spehr,
• José G. Hernández and
• Carsten Bolm

Beilstein J. Org. Chem. 2019, 15, 811–817, doi:10.3762/bjoc.15.78

• separation by column chromatography. A 5-fold scaled up version of the reaction using 3.37 mmol of 1 was carried out in a planetary ball mill (PBM) using 45 mL milling containers at 600 rpm, under otherwise identical conditions to afford product 2 in a similar yield. With TBDMS-protected glycidol 2 in our

• DAGs; PG = protecting group. Protection of glycidol (1) with TBDMSCl in the ball mill. MM = mixer mill, PBM = planetary ball mill. Cobalt-catalyzed epoxide ring-opening in the ball mill. Mechanosynthesis of DAGs 5. Conjugation of DAG 5a with 7-hydroxycoumarin (9). Supporting Information Supporting

Mechanochemistry of nucleosides, nucleotides and related materials

• Olga Eguaogie,
• Joseph S. Vyle,
• Patrick F. Conlon,
• Manuela A. Gîlea and
• Yipei Liang

Beilstein J. Org. Chem. 2018, 14, 955–970, doi:10.3762/bjoc.14.81

• (Figure 1b), an improvised attritor-type device (Figure 1c) or a planetary ball mill (not shown). The amount of mechanical energy delivered to the reaction mixture via these collisions is a function of several engineering parameters including: the frequency of vibration; the degree of filling of the

• isolated. Subsequently, Patil and Kartha described the gram-scale preparation of 5′-tritylated uridine derivatives in a planetary ball mill (using a steel vessel and balls) in the absence of TBAB [40]. Following extended grinding (600 rpm for 15 hours) of the nucleoside in the presence of excess DABCO and

A mechanochemical approach to access the proline–proline diketopiperazine framework

• Nicolas Pétry,
• Hafid Benakki,
• Eric Clot,
• Pascal Retailleau,
• Farhate Guenoun,
• Fatima Asserar,
• Chakib Sekkat,
• Thomas-Xavier Métro,
• Jean Martinez and
• Frédéric Lamaty

Beilstein J. Org. Chem. 2017, 13, 2169–2178, doi:10.3762/bjoc.13.217

• ). Finally, we tested the planetary ball mill (pbm) with the advantage of its capacity to produce more material. In this case (Table 2, entry 8), using cheaper K2CO3, full conversion was obtained and cis-11 was isolated in 75% yield and a larger amount of cis-11 could be prepared. Interestingly the cis/trans

Mechanochemical synthesis of small organic molecules

• Tapas Kumar Achar,
• Anima Bose and
• Prasenjit Mal

Beilstein J. Org. Chem. 2017, 13, 1907–1931, doi:10.3762/bjoc.13.186

• developed a mechanochemical synthesis of an indole moiety via a Rh-catalyzed C–H functionalization strategy under planetary ball mill [187]. Using acetanilide and diphenylacetylene as the alkyne component in presence of 5 mol % Rh catalyst and 2.5 mol % Cu(OAc)2 and 1 atm O2 as terminal oxidant they could

Influence of the milling parameters on the nucleophilic substitution reaction of activated β-cyclodextrins

• László Jicsinszky,
• Kata Tuza,
• Giancarlo Cravotto,
• Andrea Porcheddu,
• Francesco Delogu and
• Evelina Colacino

Beilstein J. Org. Chem. 2017, 13, 1893–1899, doi:10.3762/bjoc.13.184

• effect on the nucleophilic reaction. Keywords: cyclodextrins; milling parameters; nucleophilic substitution; planetary ball mill; Introduction Their hollow structures make cyclodextrins (CDs) a class of carbohydrates that can form inclusion complexes with organic molecules, inorganic salts and complex

• . The reaction was performed in a planetary ball mill and the processing parameters were systematically varied with the aim of pointing out their influence on the nucleophilic substitution reactions in terms of rate and yield. Specifically systematic variation involved rotation speed, milling tool

• Mechanical activation in a planetary ball mill allows the studied reactions to take place at a rate higher than the corresponding reactions in solution. Indeed, the nucleophilic substitution of tosyl groups is very slow at T < 80 °C (in DMF), while in water (at 50–70 °C) the most competitive side reaction is

Solvent-free sonochemistry: Sonochemical organic synthesis in the absence of a liquid medium

• Deborah E. Crawford

Beilstein J. Org. Chem. 2017, 13, 1850–1856, doi:10.3762/bjoc.13.179

• carried out (where grinding results in degradation of the material). Finally, as with ball milling, there is potential for the scale-up of sonochemical reactions, therefore aiding in the drive towards sustainable chemistry. Typical laboratory employed planetary ball mill and ultrasonic bath. o-Vanillin in

Encaging palladium(0) in layered double hydroxide: A sustainable catalyst for solvent-free and ligand-free Heck reaction in a ball mill

• Wei Shi,
• Jingbo Yu,
• Zhijiang Jiang,
• Qiaoling Shao and
• Weike Su

Beilstein J. Org. Chem. 2017, 13, 1661–1668, doi:10.3762/bjoc.13.160

• hybrid LDHs were then reduced by hydrazine hydrate (N2H4·H2O) to obtain the Pd catalyst supported on MgAl-LDHs (Pd/MgAl-LDHs). The as-prepared Pd/MgAl-LDH catalyst was further applied in representative cross-coupling Heck reactions under HSBM conditions (Scheme 1) by using a planetary ball mill

Mechanochemical synthesis of graphene oxide-supported transition metal catalysts for the oxidation of isoeugenol to vanillin

• Ana Franco,
• Sudipta De,
• Alina M. Balu,
• Araceli Garcia and
• Rafael Luque

Beilstein J. Org. Chem. 2017, 13, 1439–1445, doi:10.3762/bjoc.13.141

• materials, reduced graphene oxide (RGO) support, together with an appropriate amount of the iron precursor (FeCl2∙4H2O) to reach a theoretical 1% iron loading, was ground by using a Retsch-PM-100 planetary ball mill with a 25 mL reaction chamber and 8 mm stainless steel ball. Milling was conducted at 350

Nucleophilic displacement reactions of 5′-derivatised nucleosides in a vibration ball mill

• Olga Eguaogie,
• Patrick F. Conlon,
• Francesco Ravalico,
• Jamie S. T. Sweet,
• Thomas B. Elder,
• Louis P. Conway,
• Marc E. Lennon,
• David R. W. Hodgson and
• Joseph S. Vyle

Beilstein J. Org. Chem. 2017, 13, 87–92, doi:10.3762/bjoc.13.11

• liquid [13][14][15]. Recently, Jicsinszky et al. described using a planetary ball mill to perform substitution reactions of 6I-O-(p-toluenesulfonyl)-β-cyclodextrin (Ts-β-CD) with azide, halide or thiolate nucleophiles and thereby avoided intramolecular cyclisation (commonly found under solution-phase

• conditions) [16]. Following Sikchi and Hultin’s original description of nucleoside derivatisation in a low-energy, planetary ball mill [17], commercial, higher energy vibration mills have been used to facilitate established [18][19][20][21] and unprecedented [22] nucleoside transformations. Remarkably, SN2

Efficient mechanochemical synthesis of regioselective persubstituted cyclodextrins

• Laszlo Jicsinszky,
• Marina Caporaso,
• Katia Martina,
• Emanuela Calcio Gaudino and
• Giancarlo Cravotto

Beilstein J. Org. Chem. 2016, 12, 2364–2371, doi:10.3762/bjoc.12.230

• -6-substituted cyclodextrin derivative syntheses have been effectively carried out in a planetary ball mill under solvent-free conditions. The preparation of Bridion® and important per-6-amino/thiocyclodextrin intermediates without polar aprotic solvents, a source of byproducts and persistent

• millimolar scale, they are easily scalable. Keywords: green chemistry; nucleophilic substitution; planetary ball mill; siRNA delivery intermediate; sugammadex; Introduction Cyclodextrins (CDs) are cyclic α(1→4)glucopyranosides and have been fully described in a number of publications [1][2][3]. They are

• positive balance in cost-benefit analyses. Wet grinding for the preparation of per-6-azido-CDs, using solubilizing and non-solubilizing solvents, showed practically no reaction in the planetary ball mill. Important intermediates and final products of per-6-amino- and per-6-thio-CDs can be prepared without

Solvent-free, visible-light photocatalytic alcohol oxidations applying an organic photocatalyst

• Martin Obst and
• Burkhard König

Beilstein J. Org. Chem. 2016, 12, 2358–2363, doi:10.3762/bjoc.12.229

• for the investigation of our solvent-free principle. In mechanochemistry, reactions are performed by grinding the reaction mixture in ball mills, such as the vibrational ball mill or the planetary ball mill, or with a pestle and mortar. In preliminary studies, we tested a vibrational ball mill for

Mechanochemistry assisted asymmetric organocatalysis: A sustainable approach

• Pankaj Chauhan and
• Swapandeep Singh Chimni

Beilstein J. Org. Chem. 2012, 8, 2132–2141, doi:10.3762/bjoc.8.240

• solvent-free conditions by using a planetary ball mill (Scheme 7) [46]. Cinchona-derived chiral squaramide IX, at low catalyst loading of 0.5 mol %, efficiently catalyses the solvent-free Michael reaction of acetylacetone (9) with various substituted nitroalkenes 7 in a short reaction time (5–30 minutes

Solvent-free and time-efficient Suzuki–Miyaura reaction in a ball mill: the solid reagent system KF–Al₂O₃ under inspection

• Franziska Bernhardt,
• Ronald Trotzki,
• Tony Szuppa,
• Achim Stolle and
• Bernd Ondruschka

Beilstein J. Org. Chem. 2010, 6, No. 7, doi:10.3762/bjoc.6.7

• mechanical manner by co-grinding the reactants with agate milling balls using a planetary ball mill as the source for alternative energy input [4][5][6][9][36][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56]. It is worth mentioning that all results presented in this paper were achieved by

• without further purification. SRS4a and SRS5a were purchased from Sigma-Aldrich (cf. Supporting Information File 1) and used without further pre-treatment. Ball milling was conducted using the planetary ball mill “Pulverisette 7 classic line” (Fritsch GmbH, Germany). For balancing, two grinding beakers (V

• ; 5 mmol), phenylboronic acid (1; 6.19 mmol, 0.755 g, 124 mol %), Pd(OAc)2 (0.18 mmol, 0.04 g, 3.56 mol %) were added to the grinding beaker (agate, V = 45 ml) already equipped with the milling balls (6× agate, d = 15 mm) and placed inside the planetary ball mill Pulverisette 7 (Fritsch GmbH, Germany