A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in “click” reactions

• Pezhman Shiri and
• Jasem Aboonajmi

Beilstein J. Org. Chem. 2020, 16, 551–586, doi:10.3762/bjoc.16.52

• . This solid material was washed with MeOH and dried. The resulting GO/intrinsically microporous polymer (Pim) material and CuSO4 were added into water and heated at 50 °C overnight to afford the material GO/Pim/Cu (100, Scheme 22). The powder was collected by filtration and washed by water/methanol. The

• polymer that contains many carboxylate groups. These functional groups can chelate Fe3O4 nanoparticles (i.e., pectin includes the Fe3O4 nanoparticles as a shell). Generally, 122 is a branched macromolecule that is found broadly in nature. The promising aspects associated with pectin are biodegradability

Photophysics and photochemistry of NIR absorbers derived from cyanines: key to new technologies based on chemistry 4.0

• Bernd Strehmel,
• Christian Schmitz,
• Ceren Kütahya,
• Yulian Pang,
• Anke Drewitz and
• Heinz Mustroph

Beilstein J. Org. Chem. 2020, 16, 415–444, doi:10.3762/bjoc.16.40

• processes requesting heat to initiate either chemical (activated reactions) or physical (melting, evaporation) events. Keywords: chemistry 4.0; cyanine; near infrared; photopolymer; polymer synthesis; sensitizer; Introduction Cyanines have received in the class of polymethines big attention within the

• received remarkable attention in the academic community although industrial applications use this reaction to pattern imaged areas [97][98]. The structure was confirmed by direct synthesis following a procedure using MnO2[63]. Polymer synthesis NIR sensitized radical photopolymerization Photosensitized

• been in progress. Tailor-made synthesis by photo-ATRP with NIR sensitizers NIR absorbers/sensitizers have also reached the field of polymer synthesis; that is controlled/living radical polymerization (CLRP). This facilitates well-defined polymeric materials with pre-design architectures, predetermined

Room-temperature Pd/Ag direct arylation enabled by a radical pathway

• Amy L. Mayhugh and
• Christine K. Luscombe

Beilstein J. Org. Chem. 2020, 16, 384–390, doi:10.3762/bjoc.16.36

• growth are the expensive, toxic, and energy-intensive methods in which these materials are typically prepared [1]. Direct arylation is one solution to these problems, which allows improved atom and step economy in polymer synthesis. Traditional coupling methods form a new C–C bond using a reactive C–M

• number average molecular weight of 14 kg/mol, although in 9% yield [7]. Room-temperature DArP would improve the simplicity of conjugated polymer synthesis, and reduce the energy requirements. Small molecule reactions can help predict a method’s utility in polymerizations, as DArP proceeds through a step

• paper, we investigated the mechanism of room-temperature direct arylation and DArP by extending the method reported by Larrosa to synthesize a conjugated polymer, polyindole (PIn). Small molecule mechanistic studies were undertaken that will help future development of mild, efficient DArP conditions

Oligomeric ricinoleic acid preparation promoted by an efficient and recoverable Brønsted acidic ionic liquid

• Fei You,
• Xing He,
• Song Gao,
• Hong-Ru Li and
• Liang-Nian He

Beilstein J. Org. Chem. 2020, 16, 351–361, doi:10.3762/bjoc.16.34

• biomass provides an alternative avenue to liberate us from the reliance on petroleum resource [1]. Nowadays, fuels, fine chemicals and functional molecules/materials can be derived from biomass such as lignocellulose and plant oils [2][3], wherein the plant oils play an important role in the polymer

p-Pyridinyl oxime carbamates: synthesis, DNA binding, DNA photocleaving activity and theoretical photodegradation studies

• Panagiotis S. Gritzapis,
• Panayiotis C. Varras,
• Nikolaos-Panagiotis Andreou,
• Katerina R. Katsani,
• Konstantinos Dafnopoulos,
• George Psomas,
• Zisis V. Peitsinis,
• Alexandros E. Koumbis and
• Konstantina C. Fylaktakidou

Beilstein J. Org. Chem. 2020, 16, 337–350, doi:10.3762/bjoc.16.33

• under reflux were identical, meaning that no isomerization or decomposition occurred and that the delivered product in both cases is the more thermodynamically stable. Interestingly, although carbamates are important in both medicinal and polymer chemistry, besides compound 23 [61], all the rest were

Formal preparation of regioregular and alternating thiophene–thiophene copolymers bearing different substituents

• Atsunori Mori,
• Keisuke Fujita,
• Chihiro Kubota,
• Toyoko Suzuki,
• Kentaro Okano,
• Takuya Matsumoto,
• Takashi Nishino and
• Masaki Horie

Beilstein J. Org. Chem. 2020, 16, 317–324, doi:10.3762/bjoc.16.31

• and KF-404HQ. Molecular weights and molecular weight distributions were estimated on the basis of the calibration curve obtained by 6 standard polystyrenes. UV–vis absorption spectra of the polymer films were measured with a Shimadzu UV-3150 spectrometer. XRD analysis was carried out with a Rigaku

• , 1134, 1052, 840, 801, 773, 754, 720, 700 cm−1. Solubility tests of alternating copolymer 6 (1 mg of material dissolved in 1 mL of the solvent). XRD measurement and prediction of the bilayer lamellar structure of polymer 6c. a) XRD analysis. b) Suggested bilayer lamellar structure. c) Side chain length

Halogen-bonding-induced diverse aggregation of 4,5-diiodo-1,2,3-triazolium salts with different anions

• Xingyu Xu,
• Shiqing Huang,
• Zengyu Zhang,
• Lei Cao and
• Xiaoyu Yan

Beilstein J. Org. Chem. 2020, 16, 78–87, doi:10.3762/bjoc.16.10

• dimers, respectively, while the former shows boat conformation and the latter forms rectangle conformation. Triazolium salts form a linear polymer with polyiodide. Keywords: aggregation; 4,5-diiodo-1,2,3-triazolium salts; halogen bond; non-covalent interaction; Introduction The halogen bond (XB) is a

• acetate exist as dimers, respectively, while the former shows a boat conformation and the latter forms a rectangle conformation. Triazolium salts form a linear polymer with polyiodide. Results and Discussion Recently, we found that 4-iodotriazolylidene can be prepared by the treatment of a 4,5

• the former shows a boat conformation and the latter forms a rectangle conformation. Triazolium salts form a linear polymer with polyiodide. 2-BF4 forms co-crystals with 4,4'-bipyridine via halogen bonding. DFT calculation results show that the σ holes of 4,5-diiodo-1,2,3-triazolium is similar to the σ

Carbazole-functionalized hyper-cross-linked polymers for CO₂ uptake based on Friedel–Crafts polymerization on 9-phenylcarbazole

• Dandan Fang,
• Xiaodong Li,
• Meishuai Zou,
• Xiaoyan Guo and
• Aijuan Zhang

Beilstein J. Org. Chem. 2019, 15, 2856–2863, doi:10.3762/bjoc.15.279

• , as well as the C/N ratio, which has been confirmed by elemental analysis. Elemental analyses were measured to compare the degree of crosslinking of P1–P11 (Table 3), because the C/N ratio of the polymer will increase as the degree of crosslinking increases. The effect of molar ratio of cross-linker

• the polymer CZB (with similar carbazole monomer) [18]. All that reveal that enough and suitable cross-linker amount was the premise of superior specific surface areas. The effect of reaction temperature T1 on the porosity of HCPs (P3, P6, P7) The reaction temperature can mainly influence the

• than many carbazole-based HCPs with similar BET specific surface area [19][20][24]. We conjecture that the concentration of FDA can affect the formation process and morphology of the polymers, when polymer particles agglomerate and stack together (Figure 4). We reached the conclusion that when varying

Progress in metathesis chemistry

• Karol Grela and
• Anna Kajetanowicz

Beilstein J. Org. Chem. 2019, 15, 2765–2766, doi:10.3762/bjoc.15.267

• reflected by a growing number of new industrial openings. No new metathesis-based biorefineries have been built, while the traditional polymer industry seems to prefer ill-definied catalysts, and sadly, no new drugs are being produced by metathesis. On the contrary, Janssen Therapeutics recently announced

A review of asymmetric synthetic organic electrochemistry and electrocatalysis: concepts, applications, recent developments and future directions

• Munmun Ghosh,
• Valmik S. Shinde and
• Magnus Rueping

Beilstein J. Org. Chem. 2019, 15, 2710–2746, doi:10.3762/bjoc.15.264

• a small amount of inducing agents. However, poor coverage of the electrode surface with the chiral species was soon noted as one of the major disadvantages of this method, and chemists started developing polymer-coated electrodes as an alternative. In 1983, Nonaka et al. explored the applicability

Fluorinated maleimide-substituted porphyrins and chlorins: synthesis and characterization

• Valentina A. Ol’shevskaya,
• Elena G. Kononova and
• Andrei V. Zaitsev

Beilstein J. Org. Chem. 2019, 15, 2704–2709, doi:10.3762/bjoc.15.263

• ; porphyrin; spectral characteristics; synthesis; Introduction Porphyrins belong to a broad class of the natural and synthetic macroheterocyclic compounds with unique properties. They play an important role in photosynthesis [1], catalysis [2][3], nonlinear optics [4][5], polymer synthesis [6] and energy

Probing of local polarity in poly(methyl methacrylate) with the charge transfer transition in Nile red

• Aydan Yadigarli,
• Qimeng Song,
• Sergey I. Druzhinin and
• Holger Schönherr

Beilstein J. Org. Chem. 2019, 15, 2552–2562, doi:10.3762/bjoc.15.248

• permittivity of polymers and its spatial distribution play a crucial role in the behavior of thin films, such as those used, e.g., as sensor coatings. In an attempt to develop a conclusive approach to determine these quantities, the polarity of the model polymer poly(methyl methacrylate) (PMMA) in 600 nm thin

• NR molecules in the ground state and slow sub-glass transition (Tg) relaxations in PMMA. Keywords: charge transfer; dipole moment; fluorescence; inhomogeneous broadening; oxazine dye; polarity probe; polymer permittivity; Introduction The chain and segment mobility as well as the permittivity of

• polymers possess an enormous impact on the properties of polymers and polymer thin films. For ultrathin films, in which the film thickness is in the order of the radius of gyration, special effects of confinement have been observed. Prominent examples are the properties of substrate-supported ultrathin

Formation of alkyne-bridged ferrocenophanes using ring-closing alkyne metathesis on 1,1’-diacetylenic ferrocenes

• Celine Bittner,
• Dirk Bockfeld and
• Matthias Tamm

Beilstein J. Org. Chem. 2019, 15, 2534–2543, doi:10.3762/bjoc.15.246

• with high yields whilst giving full conversion of the terminal alkynes. Furthermore, the solvent-dependant reactivity of 2a towards Ag(SbF6) is investigated, leading to oxidation and formation of the ferrocenium hexafluoroantimonate 4 in dichloromethane, whereas the silver(I) coordination polymer 5 was

• can be seen in Figure 9. Single crystals of the silver complex 5 suitable for X-ray diffraction analysis could be obtained after layering a THF solution with hexane. The resulting ORTEP drawing is shown in Figure 10. The molecular structure of 5 turned out to be a coordination polymer with a rather

• reactivity of 2a towards Ag(SbF6) was investigated. It was found that this reaction is solvent dependant, and 2a was readily oxidized in DCM solution to the corresponding ferrocenium hexafluoroantimonate 4, whereas the silver(I) coordination polymer 5 was isolated from the reaction in THF solution. This

Thermal stability of N-heterocycle-stabilized iodanes – a systematic investigation

• Andreas Boelke,
• Yulia A. Vlasenko,
• Mekhman S. Yusubov,
• Boris J. Nachtsheim and
• Pavel S. Postnikov

Beilstein J. Org. Chem. 2019, 15, 2311–2318, doi:10.3762/bjoc.15.223

• alkyl and aryl radicals through thermogravimetry [16][17]. In 2013 Kumar and co-workers compared the thermal properties of open-chained aryl-λ3-iodanes with their polymer bound derivatives and found an endothermic decomposition behavior [18]. In the same year Haller and co-workers investigated the

An overview of the cycloaddition chemistry of fulvenes and emerging applications

• Ellen Swan,
• Kirsten Platts and
• Anton Blencowe

Beilstein J. Org. Chem. 2019, 15, 2113–2132, doi:10.3762/bjoc.15.209

• , allowing continuous modification through bond formation and/or breaking. This dynamic nature facilitates reorganisation through the exchange of building blocks, or incorporation of new substituents, even after the initial polymer has been formed [192]. The fulvene DAC is a good candidate for dynamer

Attempted synthesis of a meta-metalated calix[4]arene

• Christopher D. Jurisch and
• Gareth E. Arnott

Beilstein J. Org. Chem. 2019, 15, 1996–2002, doi:10.3762/bjoc.15.195

• Christopher D. Jurisch Gareth E. Arnott Department of Chemistry and Polymer Science, Stellenbosch University, Private Bag X1, Matieland, 7602, South Africa 10.3762/bjoc.15.195 Abstract An evidence for the formation of a rare meta-metalated inherently chiral calix[4]arene is described. Our

Morphology-tunable and pH-responsive supramolecular self-assemblies based on AB₂-type host–guest-conjugated amphiphilic molecules for controlled drug delivery

• Yang Bai,
• Cai-ping Liu,
• Di Chen,
• Long-hai Zhuo,
• Huai-tian Bu and
• Wei Tian

Beilstein J. Org. Chem. 2019, 15, 1925–1932, doi:10.3762/bjoc.15.188

• supramolecular self-assemblies. In the abovementioned self-assemblies; however, host and guest units have to be synthesized individually, or were incorporated into different moieties or polymer chains as terminal or side groups. Thus, the preparation procedures of the stimuli-responsive supramolecular self

Halide metathesis in overdrive: mechanochemical synthesis of a heterometallic group 1 allyl complex

• Ross F. Koby,
• Nicholas R. Rightmire,
• Nathan D. Schley,
• Timothy P. Hanusa and
• William W. Brennessel

Beilstein J. Org. Chem. 2019, 15, 1856–1863, doi:10.3762/bjoc.15.181

• ]∞ in low yield, which was crystallographically characterized as a coordination polymer that displays site disorder of the K+ and Cs+ ions. The entropic benefits of mixed Cs/K metal centers, but more importantly, the generation of multiple intermolecular K…CH3 and Cs…CH3 interactions in [CsKA'2

• coordination polymer. Within these experimental parameters, the general reaction in Equation 5 was examined. When n = 1, a reaction carried to completion would result in full metal exchange, with partial exchange the outcome for any larger values of n. The experimental protocol involved grinding various ratios

• noted that both [KA'] and CsI are insoluble in hexanes, and the grinding clearly initiated a reaction that occurred before the first hexanes extraction. Structure of [CsKA'2] Small blocks grown from hexanes were identified from a single crystal X-ray study as the coordination polymer [CsKA'2]∞. A

Synthesis of a [6]rotaxane with singly threaded γ-cyclodextrins as a single stereoisomer

• Jason Yin Hei Man and
• Ho Yu Au-Yeung

Beilstein J. Org. Chem. 2019, 15, 1829–1837, doi:10.3762/bjoc.15.177

• , cyanine and azobenzene have also been reported [18][19][20][21][22][23][24]. High order oligorotaxanes with a multiple number of α- or β-CDs threaded through polymer chains have also been prepared [25][26][27][28]. The interlocked CDs have been shown to provide an interesting insulating effect to π

Metal-free mechanochemical oxidations in Ertalyte^® jars

• Andrea Porcheddu,
• Francesco Delogu,
• Lidia De Luca,
• Claudia Fattuoni and
• Evelina Colacino

Beilstein J. Org. Chem. 2019, 15, 1786–1794, doi:10.3762/bjoc.15.172

• : multifunctional polymer composites based on grown materials). A. P. is grateful to MIUR for “Finanziamento delle Attività Base di Ricerca (FABR 2017)“.

Host–guest interactions in nor-seco-cucurbit[10]uril: novel guest-dependent molecular recognition and stereoisomerism

• Xiaodong Zhang,
• Wei Wu,
• Zhu Tao and
• Xin-Long Ni

Beilstein J. Org. Chem. 2019, 15, 1705–1711, doi:10.3762/bjoc.15.166

• adamantaneammonium (ADA) or alkylammonium ions into the cavity, forming a ternary complex. The novel binding capacity of NS-CB[10] has been utilized to form supramolecular polymers [24][25][26] and polymer nanoparticles [27]. More importantly, Isaacs et al. discovered that when the unsymmetrical guest ADA molecules

Mechanochemistry II

• José G. Hernández

Beilstein J. Org. Chem. 2019, 15, 1521–1522, doi:10.3762/bjoc.15.154

• find contributions from renowned global experts in the field of mechanochemistry spanning areas from organic mechanochemistry, supramolecular mechanochemistry to polymer mechanochemistry. Moreover, findings reported in this current thematic issue also contribute to the expansion of synthetic chemistry

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

• only those based on epichlorohydrin, have been reported, their accessibility even on a kg-scale is very limited. The spread of insoluble polymer use can be easily improved by the existence of a readily transferable and engineered method, which would eliminate the main limiting factors of solution

• ratio of CDs/epichlorohydrin was set to 1:10, which was based on the preparation of a soluble polymer [44]. Surprisingly, insoluble CDPs were almost exclusively formed at this molar ratio, unlike in the solution method. This result suggests that, in accordance with the practice, the soluble polymer

• considered negligible. Salt formation in the 10-fold scaled-up synthesis of the β-CD polymer resulted in some materials that became stuck on the jar wall. However, these were considerably easier to remove than the salts of hydrated CDs. The scale-up experiment (20 mmol scale) did not give a significantly

Reversible end-to-end assembly of selectively functionalized gold nanorods by light-responsive arylazopyrazole–cyclodextrin interaction

• Maximilian Niehues,
• Patricia Tegeder and
• Bart Jan Ravoo

Beilstein J. Org. Chem. 2019, 15, 1407–1415, doi:10.3762/bjoc.15.140

• 20-fold higher binding constant to β-CD (6.5 × 104 M−1) [32] than unmodified azobenzenes (2.5 × 103 M−1) [33]. Therefore, the competitive binding of CTAB to β-CD has been applied previously, e.g., in sensing applications [34] or to enhance the water solubility of a cyclodextrin polymer [35]. On

Complexation of a guanidinium-modified calixarene with diverse dyes and investigation of the corresponding photophysical response

• Yu-Ying Wang,
• Yong Kong,
• Zhe Zheng,
• Wen-Chao Geng,
• Zi-Yi Zhao,
• Hongwei Sun and
• Dong-Sheng Guo

Beilstein J. Org. Chem. 2019, 15, 1394–1406, doi:10.3762/bjoc.15.139

• Yu-Ying Wang Yong Kong Zhe Zheng Wen-Chao Geng Zi-Yi Zhao Hongwei Sun Dong-Sheng Guo College of Chemistry, Key Laboratory of Functional Polymer Materials, State Key Laboratory of Elemento-Organic Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Nankai University, Tianjin