Microelectrode arrays, electrosynthesis, and the optimization of signaling on an inert, stable surface

• Kendra Drayton-White,
• Siyue Liu,
• Yu-Chia Chang,
• Sakashi Uppal and
• Kevin D. Moeller

Beilstein J. Org. Chem. 2022, 18, 1488–1498, doi:10.3762/bjoc.18.156

• for the confinement strategy to keep up. The result is a loss in confinement. It is important to point out that the reaction shown in Scheme 1 is not a typical electrosynthetic reaction. The cross-coupling reaction shown is a Cu(I)-catalyzed transformation that requires no recycling of a reagent

Automated grindstone chemistry: a simple and facile way for PEG-assisted stoichiometry-controlled halogenation of phenols and anilines using N-halosuccinimides

• Dharmendra Das,
• Akhil A. Bhosle,
• Amrita Chatterjee and
• Mainak Banerjee

Beilstein J. Org. Chem. 2022, 18, 999–1008, doi:10.3762/bjoc.18.100

• ][23][24][25][26][27][28][29][30][31]. Among them, the use of N-halosuccinimides has turned out to be a viable alternative to X2 because of their low-cost, ease of handling, and possible recycling of the byproduct succinimide [24][25][26][27][28][29][30][31]. In several earlier cases, the bromination

First example of organocatalysis by cathodic N-heterocyclic carbene generation and accumulation using a divided electrochemical flow cell

• Daniele Rocco,
• Ana A. Folgueiras-Amador,
• Richard C. D. Brown and
• Marta Feroci

Beilstein J. Org. Chem. 2022, 18, 979–990, doi:10.3762/bjoc.18.98

• molecular oxygen, or electrochemically generated superoxide (cathodic reduction of O2), which oxidize the Breslow intermediate [30][39]. In fact, the presence of some reactive oxygen species in the reaction environment was previously demonstrated by the formation of compound 1b (see Table 1). IL Recycling

• were continuously passed (recycling method) through their respective compartments at a flow rate of 36 mL/min. After consumption of the requisite amount of charge (Faradays per mol of BMImBF4 reported in Table 1), the current was switched off, the flow stopped, and elemental sulfur (2.0 mmol) was added

• M of BMImBF4 in acetonitrile as catholyte and for anolyte solution see Table 2, which were passed (recycling method) in their compartments with a flow rate of 36 mL/min. After the consumption of the number of Faradays per mol of BMImBF4 reported in Table 2, the current was switched off, the flow

Shift of the reaction equilibrium at high pressure in the continuous synthesis of neuraminic acid

• Jannis A. Reich,
• Miriam Aßmann,
• Kristin Hölting,
• Paul Bubenheim,
• Jürgen Kuballa and
• Andreas Liese

Beilstein J. Org. Chem. 2022, 18, 567–579, doi:10.3762/bjoc.18.59

• recycling steps, and were characterized regarding the reaction kinetics (initial rate) and scalability (different lab scales) in a batch reactor. The reaction kinetics were studied in a continuous flow reactor. A high-pressure circular reactor (up to 130 MPa) was applied for the investigation of changes in

• methacrylate, and macroporous styrene (Figure 6). All carriers show high suitability for repeated application with the highest loss of activity (35%) for the epoxy butyl methacrylate carrier and macroporous styrene carrier (25%). Both enzymes showed a suitable reusability in the recycling study. Due to the

• (Table 2). After 50 repetitive batches, both enzymes show almost no loss of activity in the recycling study. The residual activity remains in a range around the initial activity, indicating a high robustness of the selected preparations (Figure 7). The high fluctuation of the relative activity values can

The asymmetric Henry reaction as synthetic tool for the preparation of the drugs linezolid and rivaroxaban

• Martin Vrbický,
• Karel Macek,
• Jaroslav Pochobradský,
• Jan Svoboda,
• Miloš Sedlák and
• Pavel Drabina

Beilstein J. Org. Chem. 2022, 18, 438–445, doi:10.3762/bjoc.18.46

• catalysts based on copper(II) complexes with chiral nitrogen ligands were chosen. Generally, chiral copper complexes possess many advantages valuable for the pharmaceutical industry. They exhibit low toxicity (compared to other metal-based complexes) and many of them exist in forms suitable for recycling

Menadione: a platform and a target to valuable compounds synthesis

• Acácio S. de Souza,
• Ruan Carlos B. Ribeiro,
• Dora C. S. Costa,
• Fernanda P. Pauli,
• David R. Pinho,
• Matheus G. de Moraes,
• Fernando de C. da Silva,
• Luana da S. M. Forezi and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 381–419, doi:10.3762/bjoc.18.43

• generation of waste or the use of environmentally friendly conditions, and they also allow recycling catalysts without losing efficiency [67][68][70]. Kholdeeva and co-workers reported the use of 30% aqueous H2O2 as oxidant and hydrothermally stable mesoporous mesophase titanium silicates (Ti-MMM-2) as

• addition, catalyst recycling experiments showed the TiSBA-15(6) had higher catalytic stability in the liquid-phase oxidation as compared to other titanium-containing mesoporous catalysts [67]. Cavani and co-workers reported a heterogenous catalyst system for the oxidation of 2-methylnaphthol (17) using 35

Recent developments and trends in the iron- and cobalt-catalyzed Sonogashira reactions

• Surendran Amrutha,
• Sankaran Radhika and
• Gopinathan Anilkumar

Beilstein J. Org. Chem. 2022, 18, 262–285, doi:10.3762/bjoc.18.31

• in the presence of this nanoparticle catalyst. The work-up procedure of the reaction proceeded by “in-flask” extraction and allowed for easy recycling of the catalyst. By thermal gravimetric analysis the shelf life and catalyst stability could be measured. The reductant plays an important role for

Green synthesis of C5–C6-unsubstituted 1,4-DHP scaffolds using an efficient Ni–chitosan nanocatalyst under ultrasonic conditions

• Soumyadip Basu,
• Sauvik Chatterjee,
• Suman Ray,
• Suvendu Maity,
• Prasanta Ghosh,
• Asim Bhaumik and
• Chhanda Mukhopadhyay

Beilstein J. Org. Chem. 2022, 18, 133–142, doi:10.3762/bjoc.18.14

• of our mechanistic pathway, we included a mass spectrum of the crude mixture of compounds 4k and 4m in Supporting Information File 1. Both spectra point at the presence of the respective intermediate A (in the form of 4kA and 4mA) and intermediate D (in the form of 4kD and 4mD). Recycling experiment

• up to 97% using an external magnet. In a series of five reactions, the catalyst was used repeatedly without significant decrease in catalytic activity (Figure 7). The slight reduction of the yield in later reactions may have been a result of the loss of catalyst in the recycling process. Comparison

• NPs. EDX spectrum of the Ni–chitosan NPs. Synthesis of dialkyl 1,4-dihydropyridine-2,3-dicarboxylate derivatives. ORTEP representation of product 4a (CCDC 1949329). Recycling experiment of the Ni–chitosan nanocatalyst. A plausible mechanistic route for the synthesis of C5–C6-unsubstituted 1,4-DHP

Recent advances and perspectives in ruthenium-catalyzed cyanation reactions

• Thaipparambil Aneeja,
• Cheriya Mukkolakkal Abdulla Afsina,
• Padinjare Veetil Saranya and
• Gopinathan Anilkumar

Beilstein J. Org. Chem. 2022, 18, 37–52, doi:10.3762/bjoc.18.4

• without any ruthenium contamination. The attractive features of this reaction include environment-friendly conditions, effective recycling and activity of the catalyst, and high product selectivity. A plausible mechanism of this transformation is depicted in Scheme 2. Later in 2012, Nageswar et al. have

Asymmetric organocatalyzed synthesis of coumarin derivatives

• Natália M. Moreira,
• Lorena S. R. Martelli and
• Arlene G. Corrêa

Beilstein J. Org. Chem. 2021, 17, 1952–1980, doi:10.3762/bjoc.17.128

• needed to accomplish procedures that allow recycling and lower catalyst loading, intertwined with the use of green solvents, in order to provide efficient and sustainable synthesis of these important pharmacologically active compounds. Coumarin-derived commercially available drugs. Inhibition of

A comprehensive review of flow chemistry techniques tailored to the flavours and fragrances industries

• Guido Gambacorta,
• James S. Sharley and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2021, 17, 1181–1312, doi:10.3762/bjoc.17.90

• becomes inherently gratuitous, recycling and regeneration also become easier in flow as reactivation flow streams can be directed through the reactors. There are several other adventitious benefits of using solid-supported reagents in flow, for example, a “local excess” at the entry point of a column

Heterogeneous photocatalytic cyanomethylarylation of alkenes with acetonitrile: synthesis of diverse nitrogenous heterocyclic compounds

• Guanglong Pan,
• Qian Yang,
• Wentao Wang,
• Yurong Tang and
• Yunfei Cai

Beilstein J. Org. Chem. 2021, 17, 1171–1180, doi:10.3762/bjoc.17.89

• illustrate the practicability of this CN-K-based heterogeneous photocatalysis protocol, a recycling procedure was established. The CN-K was recovered via simple centrifugation after the reaction and subsequently reused. As shown in Figure 1, the CN-K catalyst could be recycled at least five times without the

• recycling. Reaction conditions: 1a (0.1 mmol, 1 equiv), 2d (0.2 mmol, 2 equiv), CH3CN (6 mL), CN-K (1 mg/mL), 2 × 24 W blue LEDs (460 ± 5 nm) without extra heating (at 40–45 °C). After each reaction, the catalyst was recovered by centrifugation and reused in the next cycle. CN-K-Catalyzed

N-tert-Butanesulfinyl imines in the asymmetric synthesis of nitrogen-containing heterocycles

• Joseane A. Mendes,
• Paulo R. R. Costa,
• Miguel Yus,
• Francisco Foubelo and
• Camilla D. Buarque

Beilstein J. Org. Chem. 2021, 17, 1096–1140, doi:10.3762/bjoc.17.86

• organometallic compounds to the iminic carbon [1][2][3]. The ready availability of both enantiomers of tert-butanesulfinamide in large-scale processes, the easy deprotection of the amine under mild acidic conditions, and a practical procedure for recycling the chiral auxiliary [4][5] have contributed to the

Recent advances in palladium-catalysed asymmetric 1,4–additions of arylboronic acids to conjugated enones and chromones

• Jan Bartáček,
• Jan Svoboda,
• Martin Kocúrik,
• Jaroslav Pochobradský,
• Alexander Čegan,
• Miloš Sedlák and
• Jiří Váňa

Beilstein J. Org. Chem. 2021, 17, 1048–1085, doi:10.3762/bjoc.17.84

• ). The results obtained were consistent with those reported by O’Reilly using a polymeric backbone with catalytic centres inside the chain [56]. The authors outlined the possibility of recycling the catalyst based on the lower critical solution temperature (LCST) of the catalytic polymer system. The

Nitroalkene reduction in deep eutectic solvents promoted by BH₃NH₃

• Chiara Faverio,
• Monica Fiorenza Boselli,
• Patricia Camarero Gonzalez,
• Alessandra Puglisi and
• Maurizio Benaglia

Beilstein J. Org. Chem. 2021, 17, 1041–1047, doi:10.3762/bjoc.17.83

• reaction was cooled to room temperature, and the product was isolated, either by adding 4 mL of water, which dissolves the DES, and extracting the nitroalkane with AcOEt, or by direct separation of the organic residue from the eutectic mixture (see below for recycling experiments and Supporting Information

• the recycling of the DES mixture was investigated (Scheme 4). The first studies moved from the standard work-up procedure for the reaction performed at 0.1 M substrate concentration, which typically involves the addition of water to dissolve the DES and a small quantity of ethyl acetate to favor the

• extraction of the product and its separation from the eutectic mixture. However, when the recycling protocol was studied, in order to reuse the DES, at the end of the reaction, water was not added, and the product was extracted by simply adding ethyl acetate and separating the upper, organic phase. The DES

Enhanced target cell specificity and uptake of lipid nanoparticles using RNA aptamers and peptides

• Roslyn M. Ray,
• Anders Højgaard Hansen,
• Maria Taskova,
• Bernhard Jandl,
• Jonas Hansen,
• Citra Soemardy,
• Kevin V. Morris and
• Kira Astakhova

Beilstein J. Org. Chem. 2021, 17, 891–907, doi:10.3762/bjoc.17.75

• of the nature of the target proteins. CCR5, a cell surface receptor, is internalized upon ligand binding before recycling back to the cell surface or processed for degradation in the lysosome [34]. On the other hand, gp120 is a viral surface protein that is involved in viral entry through

Kinetics of enzyme-catalysed desymmetrisation of prochiral substrates: product enantiomeric excess is not always constant

• Peter J. Halling

Beilstein J. Org. Chem. 2021, 17, 873–884, doi:10.3762/bjoc.17.73

• the kinetic model expected for most dehydrogenases and ketoreductases carrying out reduction of prochiral ketones. In such reactions it is usual to recycle the co-substrate, usually NADH or NADPH. To give an idea of the behaviour under co-substrate (cofactor) recycling, the reaction progress was

• simulated with concentrations of D (NAD(P)H) and Q (NAD(P)+) constant throughout the reaction. This is a fair approximation for what happens with efficient recycling. Figure 1 shows the simulated progress of a reaction for a set of plausible conditions and enzyme properties. In all cases the product ee

• conversion that might be selected for a preparative reaction. For the reactions in Figure 1, these ee values are 0.725, 0.782, 0.816, and 0.836 as D/Q is increased from 1 to 9. All of these ee values are of course substantially lower than 0.950 found at the beginning of the reaction. Under cofactor recycling

Simulating the enzymes of ganglioside biosynthesis with Glycologue

• Andrew G. McDonald and
• Gavin P. Davey

Beilstein J. Org. Chem. 2021, 17, 739–748, doi:10.3762/bjoc.17.64

• memory formation through neuromodulation of synaptic transmission [8]. Gangliosides are recycled in the lysosome through the action of glycohydrolases. The inhibition of membrane recycling has been shown to lead to an accumulation of lysosomal gangliosides resulting in neuronal death [9]. Congenital

• includes cellular transport and recycling. A limitation of the model is that it considers only absolute changes to enzyme activity, in which an activity is either off or on, which a kinetic model based on differential-equation-based rate laws [44][45][46][47][48] or stochastic kinetics [49][50] would

Valorisation of plastic waste via metal-catalysed depolymerisation

• Francesca Liguori,
• Carmen Moreno-Marrodán and
• Pierluigi Barbaro

Beilstein J. Org. Chem. 2021, 17, 589–621, doi:10.3762/bjoc.17.53

• building blocks, including monomers, oligomers or added-value chemicals, is an attractive tool for the recycling and valorisation of these materials. The present manuscript shortly reviews the most significant contributions that appeared in the field within the period January 2010–January 2020 describing

• processes, acid–base treatments as well as the production of fuels are not discussed, nor are the methods for the further upgrade of the depolymerisation products. Keywords: catalysis; depolymerisation; plastic; recycling; sustainable; Review 1. Introduction In a circular-economy perspective, wastes are

• approach deepens the concept of plastic recycling [22][23], first of all requiring a careful design of efficient and controlled depolymerisation processes. Despite of this hurdle, the implementation of effective plastics value chains through recovery, reprocessing and upgrade would be a tangible mean to

Insight into functionalized-macrocycles-guided supramolecular photocatalysis

• Minzan Zuo,
• Krishnasamy Velmurugan,
• Kaiya Wang,
• Xueqi Tian and
• Xiao-Yu Hu

Beilstein J. Org. Chem. 2021, 17, 139–155, doi:10.3762/bjoc.17.15

• center for dye degradation. Interestingly, the photodegradation rate was significantly improved (≈95%) by adding ethylenediaminetetraacetic acid (EDTA, 0.02 mM) as the hole scavenger. To evaluate the stability of the TiO2–AuNCs@β-CD catalyst, recycling experiments were conducted. These results implied

Selected peptide-based fluorescent probes for biological applications

• Debabrata Maity

Beilstein J. Org. Chem. 2020, 16, 2971–2982, doi:10.3762/bjoc.16.247

• (Figure 10C). Lysosomes tracking Lysosomes participate multiple roles including intracellular transportation, metabolism, cell membrane recycling, and apoptosis [60]. Lysosomal lumen is acidic in nature and it is required for lysosomal enzyme activities. Deviation of lysosomal functions could result in

Controlled decomposition of SF₆ by electrochemical reduction

• Sébastien Bouvet,
• Bruce Pégot,
• Stéphane Sengmany,
• Erwan Le Gall,
• Eric Léonel,
• Anne-Marie Goncalves and
• Emmanuel Magnier

Beilstein J. Org. Chem. 2020, 16, 2948–2953, doi:10.3762/bjoc.16.244

• ][7]. On the other hand, SF6 is a greenhouse gas [8]. It has indeed a global warming potential (GWP) 22,000 times greater than CO2 [9]. From an industrial point of view, this requires efficient methods of recycling or destroying SF6. This last point implies, because of its great stability, the use of

A novel and robust heterogeneous Cu catalyst using modified lignosulfonate as support for the synthesis of nitrogen-containing heterocycles

• Bingbing Lai,
• Meng Ye,
• Ping Liu,
• Minghao Li,
• Rongxian Bai and
• Yanlong Gu

Beilstein J. Org. Chem. 2020, 16, 2888–2902, doi:10.3762/bjoc.16.238

• ; heterogeneous catalyst; immobilized copper catalyst; lignosulfonate; nitrogen-containing heterocycles; solid acid; Introduction Heterogeneous metal catalysts have been continuously receiving considerable attention in the field of organic synthesis owing to the advantages of easy separation and recycling [1][2

• catalyst after ion exchange into –SO3H, enabling the catalyst to catalyze the model reactions without the addition of protonic acid. The catalyst demonstrated impressive catalytic performance in the synthesis of nitrogen-containing heterocycles, and there was no deactivation even after 6 times of recycling

• recycling (Figure 6a), LS-FAS-Cu was still capable of catalyzing the model reaction in 70% yield, indicating that the catalyst was robust and stable under the reaction conditions and could be recycled without obvious loss of catalytic activity. The slight decreasing of yield maybe caused by the mass loss of

A consensus-based and readable extension of Linear Code for Reaction Rules (LiCoRR)

• Benjamin P. Kellman,
• Yujie Zhang,
• Emma Logomasini,
• Eric Meinhardt,
• Karla P. Godinez-Macias,
• Austin W. T. Chiang,
• James T. Sorrentino,
• Chenguang Liang,
• Bokan Bao,
• Yusen Zhou,
• Sachiko Akase,
• Isami Sogabe,
• Thukaa Kouka,
• Elizabeth A. Winzeler,
• Iain B. H. Wilson,
• Matthew P. Campbell,
• Sriram Neelamegham,
• Frederick J. Krambeck,
• Kiyoko F. Aoki-Kinoshita and
• Nathan E. Lewis

Beilstein J. Org. Chem. 2020, 16, 2645–2662, doi:10.3762/bjoc.16.215

• , cytoplasm (bacteria and archaea), or lysosome (degradation, Man-6-P dephosphorylation and lysosomal glycoprotein biosynthesis [33][34] or paucimannose recycling [35]), are important constraints on glycosylation [36], therefore, the addition of this information to the Linear Code reaction rules provides

A proposed sustainability index for synthesis plans based on input provenance and output fate: application to academic and industrial synthesis plans for vanillin as a case study

• John Andraos

Beilstein J. Org. Chem. 2020, 16, 2346–2362, doi:10.3762/bjoc.16.196

• from renewable energy sources (FRE). Valorized input materials originate from renewable, recycled, or reclaimed sources. Valorized output materials are destined for recycling or reclaiming so that they may be used in the same or other chemical processes. Valorized target product refers to that portion