Photoinduced post-modification of graphitic carbon nitride-embedded hydrogels: synthesis of 'hydrophobic hydrogels' and pore substructuring

• Cansu Esen and
• Baris Kumru

Beilstein J. Org. Chem. 2021, 17, 1323–1334, doi:10.3762/bjoc.17.92

• two scenarios. The synthesis of ‘hydrophobic hydrogel’ is reported and its application in delayed cation delivery was investigated. Furthermore, pores of the initial hydrogel were modified by the formation of a secondary polymer network. Such a facile and straightforward synthetic protocol to

• , and a detailed overview has been reported by Shalom et.al. [19]. Facile tunability has rendered g-CN to be applied in visible-light-induced catalytic reactions such as water splitting [20][21][22], pollutant degradation [23][24][25][26], CO2 reduction [27][28][29], photonics [30][31] and polymer

• physical adsorption/releasing performance being under the control of intermolecular interactions. Hydrophobization might enhance the hydrophobic interactions between the dye core and the polymer network, thus releasing can be achieved in a longer term. As a last simulative experiment, cation (K+, Ca2+, Mg2

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

• offer the advantage of high surface-to-volume ratio and scalability. These systems consist of nanoparticles embedded into a porous polymer matrix. In heterogeneous catalysis, a higher particle stability and good distribution of the catalyst leads to a reduction in pressure drop alongside a stronger

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

• catalyst precipitated and was recovered by centrifugation and discarding the supernatant liquid. This process was complicated by a low catalyst loading and high phase-transition temperature leading to the loss of mass during this procedure. The authors, however, did not try the preparation of a polymer

A chromatography-free and aqueous waste-free process for thioamide preparation with Lawesson’s reagent

• Ke Wu,
• Yichen Ling,
• An Ding,
• Liqun Jin,
• Nan Sun,
• Baoxiang Hu,
• Zhenlu Shen and
• Xinquan Hu

Beilstein J. Org. Chem. 2021, 17, 805–812, doi:10.3762/bjoc.17.69

• incomparable chelating ability towards selected transition metals, and the corresponding complexes were applied in various areas such as chemical-sensor materials, tunable redox-potential complexes, polymer hybrid luminescence materials, building blocks for multinuclear complexes, and as catalysts for cross

Chiral isothiourea-catalyzed kinetic resolution of 4-hydroxy[2.2]paracyclophane

• David Weinzierl and
• Mario Waser

Beilstein J. Org. Chem. 2021, 17, 800–804, doi:10.3762/bjoc.17.68

• polymer chemistry [1][2][7][8][9], these planar chiral molecules have been very successfully used in asymmetric catalysis [3][4][10][11][12]. Accordingly, the development of methods for the asymmetric synthesis of enantiomerically pure, or at least enantiomerically enriched, derivatives that can be

[2 + 1] Cycloaddition reactions of fullerene C₆₀ based on diazo compounds

• Yuliya N. Biglova

Beilstein J. Org. Chem. 2021, 17, 630–670, doi:10.3762/bjoc.17.55

• butyric acid 209. Based on this, fullerene dimer 210 with four hydrogen bonds having a very high dimerization constant was obtained (Scheme 43). Diethyl 4-oxopimelate was used as the precursor of polymer 213. The former was converted via diacid 211 to the target methanofullerene 212, the solution of which

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

• , we will use the term “depolymerisation” to identify the “process of converting a macromolecule into (recoverable) monomers or a mixture of monomers". Another relevant definition is that of “bioplastic”, meaning “biobased polymer derived from the biomass or issued from monomers derived from the

• breakdown by the recycled polymer, the final product or the process involved further differentiates between methods, which may lead to occasional overlaps and inconsistencies [43][44]. “Reuse” is considered a zero-order recycling option, meaning “any operation by which products or components that are not

• recycling of clean, uncontaminated single-polymer materials to give products with analogous performance and applications [47]. For example, polyethylene bottles are recycled into new bottles. Similarly, in “physical recycling”, the polymeric structure of the original material is maintained, although

Annulation of a 1,3-dithiole ring to a sterically hindered o-quinone core. Novel ditopic redox-active ligands

• Sergey V. Norkov,
• Anton V. Cherkasov,
• Andrey S. Shavyrin,
• Maxim V. Arsenyev,
• Viacheslav A. Kuropatov and
• Vladimir K. Cherkasov

Beilstein J. Org. Chem. 2021, 17, 273–282, doi:10.3762/bjoc.17.26

• a chain coordination polymer, each unit consists of two NaH(hfac) molecules and one molecule of o-quinone 4 (Figure 2). The chain is constituted from sodium ions; each sodium ion is surrounded by five oxygens. Four of them belong to hfac molecules, the fifth one is a carbonyl oxygen atom of o

• from o-quinones 3, and 7–10 were generated directly before recording of EPR spectra according to the procedure described previously [56][57]. Active methylene compounds used for the preparation of gem-dithiolates. Fragment of coordination polymer chain of adduct 8 in the crystal phase. Hydrogen atoms

The preparation and properties of 1,1-difluorocyclopropane derivatives

• Kymbat S. Adekenova,
• Peter B. Wyatt and
• Sergazy M. Adekenov

Beilstein J. Org. Chem. 2021, 17, 245–272, doi:10.3762/bjoc.17.25

• ]. The radical ring-opening polymerization (RROP) provides a synthetic route to fluoropolymers, which are useful materials [91]. The RROP of gem-difluorovinylcyclopropane (90) gave mainly the polymer with an unsymmetrical repeating unit, by the cleavage of the C2–C3 bond in the ring (Scheme 44, path a

Au(III) complexes with tetradentate-cyclam-based ligands

• Ann Christin Reiersølmoen,
• Thomas N. Solvi and
• Anne Fiksdahl

Beilstein J. Org. Chem. 2021, 17, 186–192, doi:10.3762/bjoc.17.18

• -tetraazacyclotetradecane), cyclen (1,4,7,10-tetraazacyclododecane)), ethylenediamine and triethylenetetraamine derivatives. Studies of Au(III)-cyclam modified complexes have been limited to arylated [16] or polymer-bound cyclams for selective uptake of Au(III) from water [17] as well as X-ray crystal structures [18][19

Multiswitchable photoacid–hydroxyflavylium–polyelectrolyte nano-assemblies

• Alexander Zika and
• Franziska Gröhn

Beilstein J. Org. Chem. 2021, 17, 166–185, doi:10.3762/bjoc.17.17

• Alexander Zika Franziska Grohn Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM) and Bavarian Polymer Institute (BPI), Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstr. 3, D-91058 Erlangen, Germany 10.3762/bjoc.17.17 Abstract Light- and

• binding constants Kx, which are related to the free energy change ΔG and thus due to ΔG = ΔH − TΔS, also the entropy change ΔS is revealed. Table 5 summarizes the results from the full titration curve fitting. The values correlate to the binding of one monomer of the polymer to Flavy and/or photoacid. For

• (partly) disassemble in the formation of the assemblies with the polymer such that poly(allylamine) competes with the Flavy–photoacid interaction. The rearrangement that takes place then also shows that the interaction of the poly(allylamine) with Flavy and the photoacid is preferred. The competition

Supramolecular polymers with reversed viscosity/temperature profile for application in motor oils

• Jan-Erik Ostwaldt,
• Christoph Hirschhäuser,
• Stefan K. Maier,
• Carsten Schmuck and
• Jochen Niemeyer

Beilstein J. Org. Chem. 2021, 17, 105–114, doi:10.3762/bjoc.17.11

• acid (GCP) or the aminopyridine carbonyl pyrrole carboxylic acid (ACP). At low temperatures, small cyclic structures are formed. However, at elevated temperatures, a ring–chain transformation leads to the formation of a supramolecular polymer. We demonstrate that this effect is dependent on the

• temperatures, e.g., caused by engine heat. Common VIIs are based on poly(methyl acrylate) (PMA) [1]. These systems are able to increase the viscosity at elevated temperatures by increasing their hydrodynamic radius [2]. This is based on the fact that PMAs occur as coiled polymer chains with lower hydrodynamic

• radii at lower temperature, while elevating the temperature leads to uncoiling of the polymer chain [3]. This results in a larger hydrodynamic radii and thus in an increase of viscosity [4]. The quantitative description of the viscosity improvement was developed by Dean and Davis in 1929 and coined the

Supramolecular polymerization of sulfated dendritic peptide amphiphiles into multivalent L-selectin binders

• David Straßburger,
• Svenja Herziger,
• Katharina Huth,
• Moritz Urschbach,
• Rainer Haag and
• Pol Besenius

Beilstein J. Org. Chem. 2021, 17, 97–104, doi:10.3762/bjoc.17.10

• of rigid supramolecular polymers. Since multivalent sulfated supramolecular structures mimic naturally occurring L-selectin ligands, the corresponding affinity was evaluated using a competitive SPR binding assay and benchmarked to an ethylene glycol-decorated supramolecular polymer. Keywords: L

• to its functionalization with negatively charged sulfate groups. The binding behavior of dPGS to L-selectin has been thoroughly probed as dendrimer [26][27], conjugated to a polymer [28] or as amphiphilic adamantyl conjugates that are able to self-assemble on cyclodextrin vesicles [29]. Our group

• conditions, supramolecular polymer formation with a length of several hundred nanometers is observed at monomer concentrations as low as 25 µM. Evaluation of the L-selectin binding efficacy The L-selectin binding behavior of the sulfated supramolecular polymer resulting from II was assessed using a

Selected peptide-based fluorescent probes for biological applications

• Debabrata Maity

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

• polymerization reaction between polydiacetylene. PDA liposomes turn colorless to red upon formation of cross-linked liposomes. The fluorescence of the naphthimide is completely quenched due to the energy transfer from the fluorophore to the cross-linked polymer. However, addition of LPS restores the fluorescence

Dirhamnolipid ester – formation of reverse wormlike micelles in a binary (primerless) system

• David Liese,
• Hans Henning Wenk,
• Xin Lu,
• Jochen Kleinen and
• Gebhard Haberhauer

Beilstein J. Org. Chem. 2020, 16, 2820–2830, doi:10.3762/bjoc.16.232

• micelles behave similar to a polymer and can be nicely studied by rheology [12][13]. The underlying principle of wormlike micelles, which alter the rheology of the solvent is the same as for the “normal” system (micelles in water). However, the formation of wormlike micelles in organic solvents

Selective recognition of ATP by multivalent nano-assemblies of bisimidazolium amphiphiles through “turn-on” fluorescence response

• Rakesh Biswas,
• Surya Ghosh,
• Shubhra Kanti Bhaumik and
• Supratim Banerjee

Beilstein J. Org. Chem. 2020, 16, 2728–2738, doi:10.3762/bjoc.16.223

• the receptor with their complementary binding partners in the target analyte [15]. One of the ways to design multivalent systems is to connect the receptors through covalent linkages. Conjugated polymers and conjugated polymer electrolytes are prominent examples of covalently constructed multivalent

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

• syntax for succinctly describing repeating MS units. The repetition structure is denoted by curly brackets, with a prefix of repetition times inside the brackets. For example, cellulose, which is a polymer of ᴅ-glucose residues joined by β-1,4 linkages, is represented as “{nGb4}” (RR1). If a ring

Dawn of a new era in industrial photochemistry: the scale-up of micro- and mesostructured photoreactors

• Emine Kayahan,
• Mathias Jacobs,
• Leen Braeken,
• Leen C.J. Thomassen,
• Simon Kuhn,
• Tom van Gerven and
• M. Enis Leblebici

Beilstein J. Org. Chem. 2020, 16, 2484–2504, doi:10.3762/bjoc.16.202

• scaling up can be achieved by numbering up. One of the most used photomicroreactors are capillaries wrapped around a light source. Such microcapillaries can be scaled up by connecting them either in parallel or in series (Figure 3a and Figure 3b). In a previous study, five polymer-based microcapillaries

Computational tools for drawing, building and displaying carbohydrates: a visual guide

• Kanhaya Lal,
• Rafael Bermeo and
• Serge Perez

Beilstein J. Org. Chem. 2020, 16, 2448–2468, doi:10.3762/bjoc.16.199

• . Subsequently, a glycosylation model can be prepared for carbohydrate polymer simulation using the prepreader.py script. Similarly, the doglycans.py script can be used to develop models for glycoproteins and glycolipids. Together, these tools are called doGlycans toolset. Although doGlycans is highly flexible

The B & B approach: Ball-milling conjugation of dextran with phenylboronic acid (PBA)-functionalized BODIPY

• Patrizia Andreozzi,
• Lorenza Tamberi,
• Elisamaria Tasca,
• Gina Elena Giacomazzo,
• Marta Martinez,
• Mirko Severi,
• Marco Marradi,
• Stefano Cicchi,
• Sergio Moya,
• Giacomo Biagiotti and
• Barbara Richichi

Beilstein J. Org. Chem. 2020, 16, 2272–2281, doi:10.3762/bjoc.16.188

• properties of BODIPY and the biocompatibility of dextran. The BODIPY dextran nanoparticles were characterized regarding their size, morphology, polarity, and toxicity in vitro. We demonstrate the feasibility of mechanochemistry for boronic ester formation [23] to a glycan polymer as a route of conjugation

• (Figure 2B) according to the molar extinction coefficient (see Supporting Information File 1, Figure S1). Considering that dextran is a polydisperse polymer the functionalization was reported as weight ratio percent in the labeled polymer [26]. As shown in Figure 2B, a 1.6% w/w of 1 in the Dex-1b

• conjugate Dex-1b in aggregates or nanoparticles. Moreover, it is known that dye conjugation to a polymer even in small percentages can generate a large change in the environment of the chains affecting conformation and chain organization [36]. To assess the influence of hydrophobicity on the formation of

Naphthalene diimide bis-guanidinio-carbonyl-pyrrole as a pH-switchable threading DNA intercalator

• Poulami Jana,
• Filip Šupljika,
• Carsten Schmuck and
• Ivo Piantanida

Beilstein J. Org. Chem. 2020, 16, 2201–2211, doi:10.3762/bjoc.16.185

• with DNA/RNA. To study the interactions of 4 with DNA/RNA, we opted for long (>100 base pairs) polynucleotides, to ensure a large number of identical binding sites along one polymer (Table S2 in Supporting Information File 1). Thus, we used calf thymus (ct)-DNA as a typical B-helix structure with a

Synergy between supported ionic liquid-like phases and immobilized palladium N-heterocyclic carbene–phosphine complexes for the Negishi reaction under flow conditions

• Edgar Peris,
• Raúl Porcar,
• María Macia,
• Jesús Alcázar,
• Eduardo García-Verdugo and
• Santiago V. Luis

Beilstein J. Org. Chem. 2020, 16, 1924–1935, doi:10.3762/bjoc.16.159

• under continuous flow conditions. Results and Discussion Scheme 1 summarizes the synthetic approach used for the preparation of the functionalized polymers considered in this work. A commercially available PS-DVB bead-type macroporous chloromethylated polymer 1 (Merrifield resin with 20% DVB and 1.2

• corresponding Pd–NHC complexes 4a and 4b (Scheme 1) were obtained by treatment of the supported imidazolium species with Pd(OAc)2 in the presence of a base. The amount of immobilized NHC ligand was determined by elemental analysis, while the palladium loaded on the polymer was determined by ICP analyses (see

• -bromobenzoate (6) to form methyl 4-benzylbenzoate (7) was used to evaluate the activity of the palladium catalysts on polymer support (Scheme 2). The Negishi reaction is a potent cross-coupling reaction in organic chemistry. Notably, it has much value for the synthesis of fine chemicals and medicinal drugs [22

Design, synthesis and application of carbazole macrocycles in anion sensors

• Alo Rüütel,
• Ville Yrjänä,
• Sandip A. Kadam,
• Indrek Saar,
• Mihkel Ilisson,
• Astrid Darnell,
• Kristjan Haav,
• Tõiv Haljasorg,
• Lauri Toom,
• Johan Bobacka and
• Ivo Leito

Beilstein J. Org. Chem. 2020, 16, 1901–1914, doi:10.3762/bjoc.16.157

• different types of materials such as glass, crystal, or polymer. pH electrodes with glass membranes are the most used ISEs and produce highly selective responses over a wide range of concentrations. Polymeric membranes have gained popularity due to their robustness, the ability to fine-tune their properties

• and the ability to target a larger variety of ions compared to e.g. glass. Plasticizers may be required to improve transmembrane diffusion rates unless the polymer is self-plasticizing. Plasticized poly(vinyl chloride) (PVC), which was used in this study, is an example of a commonly used membrane

Three new O-isocrotonyl-3-hydroxybutyric acid congeners produced by a sea anemone-derived marine bacterium of the genus Vibrio

• Dandan Li,
• Enjuro Harunari,
• Tao Zhou,
• Naoya Oku and
• Yasuhiro Igarashi

Beilstein J. Org. Chem. 2020, 16, 1869–1874, doi:10.3762/bjoc.16.154

• -chain 3-hydroxy acids are the common building blocks with PHA, the microbial storage polymer. The structural similarities among 1–5 and PHA suggest a quite similar or even the same biosynthetic origin of these molecules, and hence a potential dehydrative modification at the hydroxy terminus of PHA. MS

Synthesis, docking study and biological evaluation of ᴅ-fructofuranosyl and ᴅ-tagatofuranosyl sulfones as potential inhibitors of the mycobacterial galactan synthesis targeting the galactofuranosyltransferase GlfT2

• Marek Baráth,
• Jana Jakubčinová,
• Zuzana Konyariková,
• Stanislav Kozmon,
• Katarína Mikušová and
• Maroš Bella

Beilstein J. Org. Chem. 2020, 16, 1853–1862, doi:10.3762/bjoc.16.152

• decaprenyl-P-P-GlcNAc-Rha, (glycolipid 2, GL2), which serves as a lipid carrier for arabinogalactan polymerization [7][8]. The latter enzyme, GlfT2, extends the product of GlfT1-catalyzed reaction, decaprenyl-P-P-GlcNAc-Rha-Galf2 (glycolipid 4, GL4), producing the lipid-linked galactan polymer [8]. Both

• synthesis of the lipid-linked galactan polymer. Complete experimental procedures, spectral characterization of all prepared compounds and copies of their 1H NMR and 13C NMR spectra are also provided. Supporting Information File 126: Experimental and analytical data. Funding The presented work was supported