Inductive heating and flow chemistry – a perfect synergy of emerging enabling technologies

• Conrad Kuhwald,
• Sibel Türkhan and
• Andreas Kirschning

Beilstein J. Org. Chem. 2022, 18, 688–706, doi:10.3762/bjoc.18.70

• dioxide (core-shell nanostructured particles), called MagSilicaTM to be used as fixed-bed materials in many different continuous flow processes (Figure 4A) [50]. These materials are excited very rapidly in a medium frequency (25 kHz) electromagnetic field, heating reaction mixtures in packed bed reactors

• conventional heating methods, coupled with shorter cycle and start-up times. Rebrov et al. also suggested that the system can be used during periods of low power consumption to reduce the load on the electrical system. 2.5 Preparation of hydrocarbons (the Fischer–Tropsch process) Monodisperse Fe@FeCo core

• shell nanoparticles as well as Fe(0) nanoparticles with a Ru(0) layer exhibit large heating capability when exposed to an external oscillating electromagnetic field. These particles combine magnetic and surface catalytic properties and thus have been employed in the Fischer–Tropsch process. The heating

Adjusting the length of supramolecular polymer bottlebrushes by top-down approaches

• Tobias Klein,
• Franka V. Gruschwitz,
• Maren T. Kuchenbrod,
• Ivo Nischang,
• Stephanie Hoeppener and
• Johannes C. Brendel

Beilstein J. Org. Chem. 2021, 17, 2621–2628, doi:10.3762/bjoc.17.175

• (Table S1, Supporting Information File 1). This strength was in the range of Elastin filaments and significantly lower as, for instance, the tensile strength of amyloid fibrils [35][39]. Overall, the observed values for the fibers corresponded well to the sensitivity to shear forces. However, the core

• –shell structure of our supramolecular systems has to be considered in this regard. For example, significant steric strains induced by the polymer chains act on the core structure, limiting the strength of the supramolecular assembly. Conclusion In conclusion, the remarkable long-term stability of BTU

Post-functionalization of drug-loaded nanoparticles prepared by polymerization-induced self-assembly (PISA) with mitochondria targeting ligands

• Janina-Miriam Noy,
• Fan Chen and
• Martina Stenzel

Beilstein J. Org. Chem. 2021, 17, 2302–2314, doi:10.3762/bjoc.17.148

• particles sizes, which was discussed in detail elsewhere [42]. Here, the best two candidates as discussed in reference [42] were used. Both systems, p(PEGMA63-co-PENAO7)-b-p(MMA)2838 PPM-NP4 and p(MPC17-co-PENAO4)-b-p(MMA)1485 MPM-NP2, resulted in spherical core-shell nanoparticles with sizes of around 80

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

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

• . Srinivasan “Fabrication of anti-poisoning core-shell TiO2 photocatalytic system through a 4-methoxycalix[7]arene film’’ pages 1–6, Copyright (2016), with permission from Elsevier. (a) Photodimerization of 6-methylcoumarin (22). (b) Catalytic cycle for the photodimerization of 22, mediated by CB[8

Synthetic approaches to bowl-shaped π-conjugated sumanene and its congeners

• Shakeel Alvi and
• Rashid Ali

Beilstein J. Org. Chem. 2020, 16, 2212–2259, doi:10.3762/bjoc.16.186

• thermoelectric properties in addition to the onigiri-type core-shell assemblies have been reported for sumanene and its derivatives. More interestingly, its application in the absorption of small molecules such as NH3, CO2, CO, and H2 using density functional theory (DFT) calculations has also been revealed [25

Heterogeneous photocatalysis in flow chemical reactors

• Christopher G. Thomson,
• Ai-Lan Lee and
• Filipe Vilela

Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125

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

Recent advances on the transition-metal-catalyzed synthesis of imidazopyridines: an updated coverage

• Gagandeep Kour Reen,
• Ashok Kumar and
• Pratibha Sharma

Beilstein J. Org. Chem. 2019, 15, 1612–1704, doi:10.3762/bjoc.15.165

Enabling technologies and green processes in cyclodextrin chemistry

• Giancarlo Cravotto,
• Marina Caporaso,
• Laszlo Jicsinszky and
• Katia Martina

Beilstein J. Org. Chem. 2016, 12, 278–294, doi:10.3762/bjoc.12.30

• derivatives by dissolving C60 in the amorphous powder obtained from the ball milled reactants and β-CD [90]. Another example that uses the energy transfer of ball milling is the preparation of MnBi/Fe-Co core/shell structured composites. However, no pure chemical reaction is used to prepare rare-earth free

Recent advances in metathesis-derived polymers containing transition metals in the side chain

• Ileana Dragutan,
• Valerian Dragutan,
• Bogdan C. Simionescu,
• Albert Demonceau and
• Helmut Fischer

Beilstein J. Org. Chem. 2015, 11, 2747–2762, doi:10.3762/bjoc.11.296

• = BPh4 or Cl). Self-assembly of these block copolymers into core–shell spherical micelles was successfully conducted and, by UV/ozonolysis or thermal pyrolysis generating antiferromagnetic CoO species, some of these micelles could be converted into inorganic nanoparticles. With the aim at extending the

Self-assemblies of γ-CDs with pentablock copolymers PMA-PPO-PEO-PPO-PMA and endcapping via atom transfer radical polymerization of 2-methacryloyloxyethyl phosphorylcholine

• Jing Lin,
• Tao Kong,
• Lin Ye,
• Ai-ying Zhang and
• Zeng-guo Feng

Beilstein J. Org. Chem. 2015, 11, 2267–2277, doi:10.3762/bjoc.11.247

• more flexible main chain and smaller cross-sectional area as compared with PHEMA. Attaching PMA to two ends of PPO-PEO-PPO imparts the resulting amphiphilic copolymers with a unique core–shell micellar structure, showing different self-assembly behavior as compared with that of PHEMA-PPO-PEO-PPO-PHEMA

• , the aggregates were formed as spherical or “core–shell” micelles or aggregates of 500–800 nm diameter, where the shell-forming PEO bent segments would effectively bury the PMA core and shield it from water. In general, surface hydrophilic γ-CDs cannot pass through the hydrophilic shell into the core

• interaction. This leads to the breakdown of the core–shell micellar structure and the exposure of uncoated PMA chains to water. Under this circumstance, the entrapped γ-CDs began to slip off and return to accommodate the PMA segments, moving over them in a randomly distributed manner along the pentablock

Chemoselective O-acylation of hydroxyamino acids and amino alcohols under acidic reaction conditions: History, scope and applications

• Tor E. Kristensen

Beilstein J. Org. Chem. 2015, 11, 446–468, doi:10.3762/bjoc.11.51

• -load homopolymers by solution copolymerization [46][47], crosslinked polymer microspheres by dispersion copolymerization [47], crosslinked polymer beads by suspension copolymerization [47][48], catalytic core–shell micelles (nanoreactors) [68], hydrophobic nanogel particles by emulsion polymerization

• [69], magnetic core-shell nanoparticles (with magnetite cores and polyacrylate shells) [70], and thermoresponsive block copolymers [71]. Such catalytic systems can exhibit excellent organocatalytic activity under aqueous conditions, and many of them can be recycled and reused. A rather unique property

Formulation development, stability and anticancer efficacy of core-shell cyclodextrin nanocapsules for oral chemotherapy with camptothecin

• Hale Ünal,
• Naile Öztürk and
• Erem Bilensoy

Beilstein J. Org. Chem. 2015, 11, 204–212, doi:10.3762/bjoc.11.22

• as CPT which may contribute to patient quality of life and drug efficacy in cancer therapy. Keywords: amphiphilic cyclodextrin; camptothecin; core-shell; nanocapsule; oral chemotherapy; Introduction Cancer is one of the major fatal diseases in the world and causes abnormal growth of cells spreading

• bioavailability of anticancer drugs should be improved [10]. Nanoparticulate drug delivery systems are promising in this field [11][12]. Nanoparticles are defined as submicron colloidal systems that include both nanospheres and nanocapsules. Nanospheres are defined as matrix systems whereas nanocapsules are core

• -shell structures consisting of an inner liquid core (which can be either aqueous or oily depending on the core material) surrounded by a polymeric wall [13][14]. Nanocapsules present many advantages, such as improving poor water solubility, maintaining drug stability by protecting the molecule from the

Linear-g-hyperbranched and cyclodextrin-based amphiphilic block copolymer as a multifunctional nanocarrier

• Yamei Zhao,
• Wei Tian,
• Guang Yang and
• Xiaodong Fan

Beilstein J. Org. Chem. 2014, 10, 2696–2703, doi:10.3762/bjoc.10.284

• and quaternization reaction. The ABC then self-assembled into stable micelles with a core–shell structure in aqueous solution. These resulting micelles are multifunctional nanocarriers which possess higher drug loading capability due to the introduction of HBPCSi segments and β-CD moieties, and

• goal of this research is to engineer a multifunctional nanocarrier for addressing the above issues simultaneously. Specifically, a novel ABC based on the linear-hyperbranched-cyclodextrin (CD) ternary system (Scheme 1A–C) was designed, which can self-assemble into the core–shell structured micelles

• chain of two PHEMA blocks via a pseudo-one-step hydrosilylation reaction. Finally, modified β-CD monomers were bonded to the amino groups of PDMAEMA block side chain by the action of ionic bonds (P3). The P3 self-assembled into stable micelles with a core–shell structure in aqueous solution. The

End-group-functionalized poly(N,N-diethylacrylamide) via free-radical chain transfer polymerization: Influence of sulfur oxidation and cyclodextrin on self-organization and cloud points in water

• Sebastian Reinelt,
• Daniel Steinke and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 680–691, doi:10.3762/bjoc.10.61

• solutions of polymer 9c, RAMEB-CD and polymer 9c in the presence of one equivalent RAMEB-CD. These results indicated that the 4-tert-alkylphenol end-groups tend to aggregate strongly leading to the formation of intermolecular core-shell micellar-like structures as stated in Figure 8. However, it should be

• of thermo-responsive micelles of end-group functionalized respectively block copolymers in aqueous solution have been investigated in previous studies [35][48][49]. Studies on hydrophobically PNIPAM have also demonstrated the formation of core-shell structures exhibiting a corona of PNIPAM chains [25

• ][35][36]. The formation of micellar-like structures lead to an isolation of the hydrophobic end-groups from water and thus to a dramatically supression of the hydrophobicity of the polymer. Due to the interaction of the polymeric end-group with RAMEB-CD the formation of these core-shell structures is

The synthesis of well-defined poly(vinylbenzyl chloride)-grafted nanoparticles via RAFT polymerization

• John Moraes,
• Kohji Ohno,
• Guillaume Gody,
• Thomas Maschmeyer and
• Sébastien Perrier

Beilstein J. Org. Chem. 2013, 9, 1226–1234, doi:10.3762/bjoc.9.139

• Sustainability, School of Chemistry, The University of Sydney, NSW 2006, Australia 10.3762/bjoc.9.139 Abstract We describe the use of one of the most advanced radical polymerization techniques, the reversible addition fragmentation chain transfer (RAFT) process, to produce highly functional core–shell particles

• , and we demonstrate that the exceptional control over their dimensions is achieved by careful tailoring the conditions of the radical polymerization. Keywords: core–shell particles; free radical; grafting; RAFT polymerization; silica; Introduction The versatility of organic free radical chemistry in

• preparing highly monodisperse core–shell nanoparticles, which hold great promise for a range of applications such as drug-delivery vectors or colloidal-crystal self-assemblies [10][11]. RAFT polymerization initiated from preformed inorganic nanoparticles enables the grafting of polymer shells from the

Simple and rapid hydrogenation of p-nitrophenol with aqueous formic acid in catalytic flow reactors

• Rahat Javaid,
• Shin-ichiro Kawasaki,
• Akira Suzuki and
• Toshishige M. Suzuki

Beilstein J. Org. Chem. 2013, 9, 1156–1163, doi:10.3762/bjoc.9.129

• catalyzed with core–shell Au–Pd NPs and Au NPs [23][24][25][26]. Formic acid is another attractive H2 source because it is safe, easy to handle, and requires no high-pressure equipment. Formic acid and formate have been used as effective H2 donors in the catalytic transfer hydrogenation of aromatic nitro

Sexithiophenes as efficient luminescence quenchers of quantum dots

• Christopher R. Mason,
• Yang Li,
• Paul O’Brien,
• Neil J. Findlay and
• Peter J. Skabara

Beilstein J. Org. Chem. 2011, 7, 1722–1731, doi:10.3762/bjoc.7.202

• , with retention of the photoluminescence behaviour of the quantum dot [24]. Herein, we present a comparative study on the photophysical properties of sexithiophenes 1 or 2 in varying concentrations, in the presence of a fixed concentration of CdSe(ZnS) core/shell quantum dots. Our choice of compounds

• ) core/shell quantum dots was conducted to determine the effect of the Lewis base group in sexithiophenes 1a and 1b. The quantum dot CdSe core was prepared by the method of Cumberland et al. [25], and the ZnS shell was added using the dithiocarbamate precursor Zn(S2CNMeHex)2 [26]. The resulting dots

Miniemulsion polymerization as a versatile tool for the synthesis of functionalized polymers

• Daniel Crespy and
• Katharina Landfester

Beilstein J. Org. Chem. 2010, 6, 1132–1148, doi:10.3762/bjoc.6.130

• water and oil, leading the authors to identify their particles as capsules (core–shell with oil as the core). Huang et al. showed that paclitaxel was encapsulated with high efficiency in poly(n-butyl cyanoacrylate) produced in miniemulsion [84]. Amino acids have been employed to initiate the

• pyrrole initiated by iron(III) chloride on polystyrene latexes produced in miniemulsion to yield particles with sizes ranging from 50 to 70 nm [96]. The conductivity of pellets prepared from the particles was found to be 15.4 S∙cm−1. Core–shell morphologies could be identified by selectively dissolving

• were also polymerized in the presence of monomers, which can be polymerized under radical conditions to yield hybrid latexes [106][107]. Li et al. showed that homogeneous or core–shell morphologies could be obtained depending on the diol added and on the location of the initiator (water-soluble versus

Gelation or molecular recognition; is the bis-(α,β-dihydroxy ester)s motif an omnigelator?

• Peter C. Griffiths,
• David W. Knight,
• Ian R. Morgan,
• Amy Ford,
• James Brown,
• Ben Davies,
• Richard K. Heenan,
• Stephen M. King,
• Robert M. Dalgliesh,
• John Tomkinson,
• Stuart Prescott,
• Ralf Schweins and
• Alison Paul

Beilstein J. Org. Chem. 2010, 6, 1079–1088, doi:10.3762/bjoc.6.123

• with the 10 Å distance, i.e., Q = 0.6 Å−1, but the data are not of sufficient quality to state whether the features at this Q are significant or not. It should be noted that a core-shell morphology was also tested, but the peak could only be reproduced by assuming unphysical parameters – a 10 Å in

Hybrid biofunctional nanostructures as stimuli-responsive catalytic systems

• Gernot U. Marten,
• Thorsten Gelbrich and
• Annette M. Schmidt

Beilstein J. Org. Chem. 2010, 6, 922–931, doi:10.3762/bjoc.6.98

• , biocompatibility, and a tunable lower critical solution temperature (LCST) in water. The phase separation can alternatively be initiated by magnetic heating caused by magnetic losses in ac magnetic fields. The immobilization of porcine pancreas trypsin to the core–shell nanoparticles results in highly active

• , nanoparticulate biocatalysts that can easily be separated magnetically. The enzymatic activity of the obtained biocatalyst system can be influenced by outer stimuli, such as temperature and external magnetic fields, by utilizing the LCST of the copolymer shell. Keywords: biocatalysis; biolabelling; core–shell

• -type shell. Synthesis of functional core–shell nanostructures In the first step, Fe3O4 nanoparticles are prepared by alkaline precipitation based on a method of Cabuil and Massart [43] and surface-functionalized with (p-chloromethyl)phenyltrimethoxysilane (CTS) [44] in order to introduce benzylic

Poly(glycolide) multi-arm star polymers: Improved solubility via limited arm length

• Florian K. Wolf,
• Anna M. Fischer and
• Holger Frey

Beilstein J. Org. Chem. 2010, 6, No. 67, doi:10.3762/bjoc.6.67

• architectures exhibit significantly altered physical properties [14][15]. This is often considered the primary motivation for the choice of this interesting polymer architecture [16]. A suitable multifunctional core molecule is required to prepare multi-arm star polymers with core–shell characteristics. Apart

• environment when core–shell topologies for encapsulation are desired. Here we present a solvent-free synthetic strategy for multi-arm star block copolymers with a hyperbranched polyether core and PGA arms, systematically varying arm length. The combination of glycolide with a multifunctional initiator studied