Radical chemistry in polymer science: an overview and recent advances

• Zixiao Wang,
• Feichen Cui,
• Yang Sui and
• Jiajun Yan

Beilstein J. Org. Chem. 2023, 19, 1580–1603, doi:10.3762/bjoc.19.116

• process is called Compton scattering [179]. One of the major purposes of radiation modification of polymer surfaces is grafting. The surface grafting can be simply tuned by the dose of radiation [180]. Radiation grafting on polymer surfaces is also compatible with RDRP for high density and well-defined

• derivatives. Chemical reaction process scheme of DCP-induced crosslinking of LDPE. Scheme 16 redrawn from [126]. A probable mechanism of radical-induced hydrosilylation. Polymer surface modification by homolytic dediazonation of diazonium salts. Photoinduced polymer surface modification or surface grafting

Construction of hexabenzocoronene-based chiral nanographenes

• Ranran Li,
• Di Wang,
• Shengtao Li and
• Peng An

Beilstein J. Org. Chem. 2023, 19, 736–751, doi:10.3762/bjoc.19.54

• reaction [39]. Recently, An and co-workers reported a helical, azepine-containing NG 27 by the introduction of an NH in the seco-HBC framwork (Scheme 3). Single-crystal X-ray diffractometry revealed the mixed P/M enantiomers. Taking advantage of the grafting NH functional group, the optical resolution of

Preparation of β-cyclodextrin/polysaccharide foams using saponin

• Max Petitjean and
• José Ramón Isasi

Beilstein J. Org. Chem. 2023, 19, 78–88, doi:10.3762/bjoc.19.7

• amount of ‘free cyclodextrin’ per gram than that of pure cyclodextrin. This may be due to a possible saponin/β-CD complexation, yielding the cyclodextrin unavailable, or because the polysaccharides enhance the grafting of cyclodextrin into their chains. It needs to be added that pure polysaccharide

Synthetic study toward tridachiapyrone B

• Morgan Cormier,
• Florian Hernvann and
• Michaël De Paolis

Beilstein J. Org. Chem. 2022, 18, 1741–1748, doi:10.3762/bjoc.18.183

• ’-methoxy-γ-pyrone in one step. To construct the quaternary carbon of the 2,5-cyclohexadienone of the target, a strategy based on the Robinson-type annulation of an aldehyde derived from α-crotyl-α’-methoxy-γ-pyrone was applied. The grafting of the simplified target’s side chain was demonstrated through an

• carbanions of 1,3-dithiane [27], allyl [27], and methyldienylbenzene groups [31] to compound 2 were demonstrated, this result amounts to the first grafting of an aromatic nucleophile to the motif. The construction of the vicinal quaternary carbon of 6b was next investigated by methylation of the highly

• was not the case, the process was poorly reproducible. On the other hand, the 1,2-addition of Grignard reagents to 5 was observed, providing thus an alternative way of grafting a side chain. As summarized in Scheme 7a, this was envisaged through a sequence encompassing the 1,2-addition of the 1,3

1,4,6,10-Tetraazaadamantanes (TAADs) with N-amino groups: synthesis and formation of boron chelates and host–guest complexes

• Artem N. Semakin,
• Ivan S. Golovanov,
• Yulia V. Nelyubina and
• Alexey Yu. Sukhorukov

Beilstein J. Org. Chem. 2022, 18, 1424–1434, doi:10.3762/bjoc.18.148

• Tripodal molecules are widely used as chelating ligands for transition metal catalysis [1][2][3], sensors for ions and small molecules [4][5], reagents for surface grafting [6], building blocks for the construction of supramolecular structures [7], polycyclic cage molecules [8], and porous materials [9

Cryogels: recent applications in 3D-bioprinting, injectable cryogels, drug delivery, and wound healing

• Luke O. Jones,
• Leah Williams,
• Tasmin Boam,
• Martin Kalmet,
• Chidubem Oguike and
• Fiona L. Hatton

Beilstein J. Org. Chem. 2021, 17, 2553–2569, doi:10.3762/bjoc.17.171

• temperature and pH. For example, grafting thermally responsive PNIPAM to a backbone of pH-responsive chitosan to produce a cryogel responsive to both temperature and pH has been explored in some detail [48][49][50][51][52], and the application as a drug-delivery system in the intestine has also been

Constrained thermoresponsive polymers – new insights into fundamentals and applications

• Patricia Flemming,
• Alexander S. Münch,
• Andreas Fery and
• Petra Uhlmann

Beilstein J. Org. Chem. 2021, 17, 2123–2163, doi:10.3762/bjoc.17.138

• responsiveness of the polymers. The switching behavior can thus be controlled not only by the chemical composition of the polymer and its chain length, but also by its specific arrangement, for example by varying the grafting density [40][41][42]. Therefore, a transfer of the physicochemical concepts valid for

• influence of grafting density, degree of crosslinking or branching as well as the substrate’s influence on the UCST phase transition of grafted polymers. Moreover, for polymers in solution, a generalized thermodynamic description and a standardized characterization of the macroscopic effects via

• geometry. In addition, each grafted film has a density- and thus a concentration profile, which makes it difficult to define a quantity corresponding to the Tcp. The exact concentration in a grafted polymer film is not known and can only be indirectly given by the grafting density. Thus, the phase

An initiator- and catalyst-free hydrogel coating process for 3D printed medical-grade poly(ε-caprolactone)

• Jochen Löblein,
• Thomas Lorson,
• Miriam Komma,
• Tobias Kielholz,
• Maike Windbergs,
• Paul D. Dalton and
• Robert Luxenhofer

Beilstein J. Org. Chem. 2021, 17, 2095–2101, doi:10.3762/bjoc.17.136

• achieved with self-initiated photografting and photopolymerization (SIPGP, Scheme 1). SIPGP is a simple, solvent-free bulk/surface photografting first introduced by Deng et al. grafting maleic anhydride [20] and styrene [21] onto low-density poly(ethylene) films. Later, this was extended for other monomers

Synthetic accesses to biguanide compounds

• Oleksandr Grytsai,
• Cyril Ronco and
• Rachid Benhida

Beilstein J. Org. Chem. 2021, 17, 1001–1040, doi:10.3762/bjoc.17.82

• benzothiazole and benzimidazole-based sulfonylguanidine compounds were derived by the sulfonylation of the corresponding 2-guanidinobenzazoles and assayed as potential antimelanoma agents (Scheme 11C) [33]. Of note, a dearomatization of the benzothiazole ring was observed while grafting a sulfoguanidinyl group

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

• prepared catalyst for synthesizing nitrogen-containing heterocycles. The results showed that the grafting of FAS on LS provided the support with more ion exchange sites, significantly increasing the loading capability of the Cu species. The acidification process could transform the –SO3Na group left in the

• , exhibiting enhanced stability compared to that without grafting of FAS. It is expected that this research would shed light on the design of heterogeneous metal catalysts with high activity and stability. Results and Discussion The whole preparation process of the catalyst is depicted in Figure 1. Firstly

• , the support was prepared through phenol–formaldehyde condensation reaction of LS and FAS. The FAS was chosen to embellish LS in consideration of the following reason: FAS skeleton consists of both aldehyde and sulfonic groups, so the grafting of FAS and LS can be easily realized via phenol

Tools for generating and analyzing glycan microarray data

• Akul Y. Mehta,
• Jamie Heimburg-Molinaro and
• Richard D. Cummings

Beilstein J. Org. Chem. 2020, 16, 2260–2271, doi:10.3762/bjoc.16.187

• thus provides a unique one-stop solution to cross referencing glycan microarray data alongside protein structure. 2. Gly-Spec (Grafting): Status: Available. Address: http://glycam.org/djdev/grafting/. Description: Gly-Spec (Grafting) uses structural data to predict glycan microarray binding [52]. In

Aldehydes as powerful initiators for photochemical transformations

• Maria A. Theodoropoulou,
• Nikolaos F. Nikitas and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2020, 16, 833–857, doi:10.3762/bjoc.16.76

• aldehydes and ketones were studied in the photografting of acrylic acids. In 1988, Allméar and co-workers, while studying the grafting of acrylic acid (34) onto high- or low-density polyethylene and polystyrene using benzophenone as the photoinitiator and acetone (4) as the solvent, observed that the

• grafting was possible even in the absence of benzophenone due to acetone (4), but at a slower rate [39]. Later, Kubota and co-workers found that acetone (4) could act as an efficient photoinitiator for photografting, in contrast to other aliphatic ketones [40]. In 2004, Wang and co-workers also observed

• acetone (4) and formaldehyde (35) in initiating the photografting in an aqueous solution. The maximum extent of grafting was observed for 10 wt % of 36. The concentration of 42 also affected the extent of photografting. The extent of grafting increased with the increase of the monomer up to 2 mol/L and

Fluorescent phosphorus dendrimers excited by two photons: synthesis, two-photon absorption properties and biological uses

• Anne-Marie Caminade,
• Artem Zibarov,
• Eduardo Cueto Diaz,
• Aurélien Hameau,
• Maxime Klausen,
• Kathleen Moineau-Chane Ching,
• Jean-Pierre Majoral,
• Jean-Baptiste Verlhac,
• Olivier Mongin and
• Mireille Blanchard-Desce

Beilstein J. Org. Chem. 2019, 15, 2287–2303, doi:10.3762/bjoc.15.221

• (Figure 12). Studies of the TPA properties demonstrated that some of these dendrimers outperform the TPA cross-section response of quantum dots, while having a much lower intrinsic toxicity, as being composed or organic matter instead of heavy metals. The grafting of water-solubilizing functions on the

Functional panchromatic BODIPY dyes with near-infrared absorption: design, synthesis, characterization and use in dye-sensitized solar cells

• Quentin Huaulmé,
• Cyril Aumaitre,
• Outi Vilhelmiina Kontkanen,
• David Beljonne,
• Alexandra Sutter,
• Gilles Ulrich,
• Renaud Demadrille and
• Nicolas Leclerc

Beilstein J. Org. Chem. 2019, 15, 1758–1768, doi:10.3762/bjoc.15.169

• were investigated using UV–vis spectroscopy, and we show that they can absorb light up to 900 nm in solution and 1000 nm in solid state, after grafting on anatase-TiO2 mesoporous films. The cyclic voltammetry (CV) measurements indicate that the compounds have HOMO and LUMO energy levels suitable for an

• ) Grafting the triphenylamine donor moieties on the thiophene-vinylene bridge only slightly (by ca. 0.1 eV) lowers the ionization potential of the dyes, compare (1,2) to (3,4); this is explained by the fact that the HOMO molecular orbital mostly spreads on the BODIPY-vinylthiophene core of the molecules

• , grafting them on the surface clearly impacts the absorption bands attributed to the BODIPY part of the systems. The absorption coefficient of the lower energy absorption band, attributed to the S0→S1 transition, is reduced and a higher energy band around 700 nm increases in intensity. This last one is more

Synthesis, enantioseparation and photophysical properties of planar-chiral pillar[5]arene derivatives bearing fluorophore fragments

• Guojuan Li,
• Chunying Fan,
• Guo Cheng,
• Wanhua Wu and
• Cheng Yang

Beilstein J. Org. Chem. 2019, 15, 1601–1611, doi:10.3762/bjoc.15.164

• of P5A-Py is 3.4 ns which is shorter than that of Py-6 (4.4 ns), demonstrating that grafting two Py units in close proximity in one host, opened a new route for nonradiative decay. This phenomenon further verified the occurrence of π–π stacking of the Py fragments in P5A-Py. The lifetime of P5A-DPA

• was 4.8 ns, which is very similar to DPA-6 (5.0 ns) and the non-substituted DPA (5.3 ns) [42]. The fact that grafting DPA units in one host did not influence the fluorescent quantum yield together with the appealing host–guest properties make P5A-DPA an ideal candidate for applications as acceptor for

• assigned to the excimer emission of Py (Figure S23, Supporting Information File 1) [54]. Conclusion Two new planar chiral macrocyclic hosts P5A-DPA and P5A-Py were synthesized by grafting two fluorophore pigments (DPA or Py) on pillar[5]arene through CuAAC “click” reaction. The new macrocyclic compounds

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

• use and high sensitivity, and has been widely used in fields of chemistry, biomedicine, environment, and so on [1]. Generally, the conversion of a luminescent dye to a chemosensor requires a grafting recognition motif for a particular analyte, whose installation often involves laborious and time

Olefin metathesis in multiblock copolymer synthesis

• Maria L. Gringolts,
• Yulia I. Denisova,
• Eugene Sh. Finkelshtein and
• Yaroslav V. Kudryavtsev

Beilstein J. Org. Chem. 2019, 15, 218–235, doi:10.3762/bjoc.15.21

• (cyclohexene carbonate)s was carried out by the β-diiminate (BDI) zinc-catalyzed block copolymerization of functionalized epoxides and CO2 with a norbornenyl-containing initiator (Scheme 5) [68]. The subsequent “grafting through” by ROMP of norbornene resulted in the synthesis of multiblock copolymer brushes

An overview on recent advances in the synthesis of sulfonated organic materials, sulfonated silica materials, and sulfonated carbon materials and their catalytic applications in chemical processes

• Hashem Sharghi,
• Pezhman Shiri and
• Mahdi Aberi

Beilstein J. Org. Chem. 2018, 14, 2745–2770, doi:10.3762/bjoc.14.253

• obtained by the 30:1 molar ratio of MeOH/oleic acid. It is well known that grafting MWCNTs with -SO3H functions is very useful for activation of catalysts. On the other hand, the most common technique to sulphonate these materials is through thermal treatment by concentrated sulfuric acid. These procedures

• before use in the reaction. This causes that the tendency of adsorption of PFAD on active sites was decreased and consequently the catalyst will not be deactivated. A covalently grafting modified nanoscaled diamond powder with 1,3-propanesultone (Scheme 26) 138 exhibited excellent catalytic activity for

Synthesis and photophysical studies of a multivalent photoreactive Ru^II-calix[4]arene complex bearing RGD-containing cyclopentapeptides

• Sofia Kajouj,
• Lionel Marcelis,
• Alice Mattiuzzi,
• Adrien Grassin,
• Damien Dufour,
• Pierre Van Antwerpen,
• Didier Boturyn,
• Eric Defrancq,
• Mathieu Surin,
• Julien De Winter,
• Pascal Gerbaux,
• Ivan Jabin and
• Cécile Moucheron

Beilstein J. Org. Chem. 2018, 14, 1758–1768, doi:10.3762/bjoc.14.150

• presented in Figure 2, as issued from a molecular dynamics (MD) simulations. The ruthenium complex and the RGD units are spatially well-separated thanks to their grafting on opposite faces of the rigid calixarene-based platform. In this conformation, the distances between the Ru atom and each of the nearest

Nanoreactors for green catalysis

• M. Teresa De Martino,
• Loai K. E. A. Abdelmohsen,
• Floris P. J. T. Rutjes and
• Jan C. M. van Hest

Beilstein J. Org. Chem. 2018, 14, 716–733, doi:10.3762/bjoc.14.61

• similar morphology [56][112]. The metal nanoparticle core is covered by polymeric brushes, the length and the grafting are important factors which can affect the reaction, as discussed in the following paragraph, and the easy manufacturing of metal nanoparticles makes the preparation of these core-brushes

Synthesis of naturally-derived macromolecules through simplified electrochemically mediated ATRP

• Paweł Chmielarz,
• Tomasz Pacześniak,
• Katarzyna Rydel-Ciszek,
• Izabela Zaborniak,
• Paulina Biedka and
• Andrzej Sobkowiak

Beilstein J. Org. Chem. 2017, 13, 2466–2472, doi:10.3762/bjoc.13.243

• macroinitiator was received for the first time by the transesterification reaction of quercetin with 2-bromoisobutyryl bromide. In accordance with the “grafting from” strategy, a naturally-occurring star-like polymer with a polar 3,3',4',5,6-pentahydroxyflavone core and hydrophobic poly(tert-butyl acrylate

• via three main strategies: “grafting onto” [5][6][7][8][9][10], “grafting through” [11][12], or “grafting from” [10][13][14][15][16][17][18][19][20][21]. The “grafting from” approach in particular, allows the tailoring of the side chain composition and the introduction of functional groups via

• ',5,6-pentahydroxyflavone-based core with 2-bromoisobutyryl bromide as initiation molecule, and grafting of the PtBA arms of the flavonoid-based moiety by facile seATRP technique. To demonstrate the possibility of temporal control, on-demand seATRP was carried out utilizing multiple-step potential

Synthesis and application of trifluoroethoxy-substituted phthalocyanines and subphthalocyanines

• Satoru Mori and
• Norio Shibata

Beilstein J. Org. Chem. 2017, 13, 2273–2296, doi:10.3762/bjoc.13.224

• TFEO-ZnPc 4 and fluorinated polymer 22 were condensed by a click reaction between azide and alkyne groups (Scheme 8). The graft ratio of the TFEO-ZnPc-supported fluoropolymer was calculated from the area ratio of 19F NMR, and the resulting fluorinated copolymers showed different grafting ratios (from

An efficient Pd–NHC catalyst system in situ generated from Na₂PdCl₄ and PEG-functionalized imidazolium salts for Mizoroki–Heck reactions in water

• Nan Sun,
• Meng Chen,
• Liqun Jin,
• Wei Zhao,
• Baoxiang Hu,
• Zhenlu Shen and
• Xinquan Hu

Beilstein J. Org. Chem. 2017, 13, 1735–1744, doi:10.3762/bjoc.13.168

• modifying traditional palladium–phosphine catalysts by grafting various hydrophilic substituents on phosphine ligands [18][19][20][21][22][23][24][25][26][27]. However, most of these phosphine ligands are air sensitive and required tedious work to preparation. In addition, the easy dissociation of common P

Kinetic analysis of mechanoradical formation during the mechanolysis of dextran and glycogen

• Naoki Doi,
• Yasushi Sasai,
• Yukinori Yamauchi,
• Tetsuo Adachi,
• Masayuki Kuzuya and
• Shin-ichi Kondo

Beilstein J. Org. Chem. 2017, 13, 1174–1183, doi:10.3762/bjoc.13.116

• approximately 95% α-D-1,6-linkages, which form a straight chain, and 5% α-1,3-linkages, from which branches begin, as shown in Figure 2 [8][9][10]. The grafting of synthetic polymers onto Dx has generally been carried out using oxygen-based radicals produced via a hydrogen abstraction method (e.g., radical

Energy down converting organic fluorophore functionalized mesoporous silica hybrids for monolith-coated light emitting diodes

• Markus Börgardts and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2017, 13, 768–778, doi:10.3762/bjoc.13.76

• synthesis of mesoporous hybrid materials by postsynthetic grafting to commercially available MCM-41. These individually dye-functionalized hybrid materials are mixed in variable ratios to furnish a powder capable of emitting white light with CIE chromaticity coordinates of x = 0.33, y = 0.33 and an external

• ; postsynthetic grafting; white light emission; Introduction The development of new efficient illumination materials has received increasing attention in the past years [1][2][3]. For the generation of white light the combination of a UV emitting light source and energy down converting phosphor emitting in the

• color temperature is possible. The synthesis of silica hybrid materials functionalized with a single dye was performed via postsynthetic grafting of commercially available MCM-41 according to literature procedures [12][13][17]. Therefore, the respective dye precursors 9, 10, and 8 at variable