Rotaxanes with integrated photoswitches: design principles, functional behavior, and emerging applications

• Jullyane Emi Matsushima,
• Khushbu,
• Zuliah Abdulsalam,
• Udyogi Navodya Kulathilaka Conthagamage and
• Víctor García-López

Beilstein J. Org. Chem. 2025, 21, 2345–2366, doi:10.3762/bjoc.21.179

• , thereby avoiding the terminal cationic sites [25]. The shuttling is restored by the thermal reaction that regenerates the neutral acridane [24][25][26]. The same group also demonstrated that similar rotaxanes can be incorporated onto gold nanoparticles and retain their photoreactivity and switching

• cannot undergo the photocyclization reaction when the macrocycle is in the BAA site due to conformational restraint. This system was used to form water-soluble nanoparticles to investigate their biological applications. The obtained nanoparticles exhibited bright red photoluminescence and the ability to

• generate singlet oxygen (¹O2), which can be controlled through dithienylethene photoisomerization. Therefore, the authors investigated these nanoparticles for bioimaging and apoptosis of HeLa cells. When the dithienylethene is in the open form, the nanoparticles have relatively high cytotoxicity due to the

C2 to C6 biobased carbonyl platforms for fine chemistry

• Jingjing Jiang,
• Muhammad Noman Haider Tariq,
• Florence Popowycz,
• Yanlong Gu and
• Yves Queneau

Beilstein J. Org. Chem. 2025, 21, 2103–2172, doi:10.3762/bjoc.21.165

Research progress on calixarene/pillararene-based controlled drug release systems

• Liu-Huan Yi,
• Jian Qin,
• Si-Ran Lu,
• Liu-Pan Yang,
• Li-Li Wang and
• Huan Yao

Beilstein J. Org. Chem. 2025, 21, 1757–1785, doi:10.3762/bjoc.21.139

• vesicles, micelles and nanoparticles, overcoming the difficulties in modifying cyclodextrin and cucurbituril. These features make CAs and PAs promising candidates for stimulus responsive drug release systems [46]. Their structural diversity and functional designability offer broad prospects for targeted

• nanoparticles [62]. Their morphologies mainly depend on molecular structure, concentration, and environmental properties. The cylindrical geometry of vesicles [63] promotes the arrangement of amphiphilic molecules with their hydrophobic tails pointing inward and hydrophilic heads pointing outward, forming a

• closed bilayer [64]. In contrast, micelles are usually assembled from single-tailed, conical molecules, where the smaller hydrophobic chains and larger head groups form monolayer spherical or rod-like structures [65]. Moreover, nanoparticles can be constructed through the physical or chemical cross

Recent advances in synthetic approaches for bioactive cinnamic acid derivatives

• Betty A. Kustiana,
• Galuh Widiyarti and
• Teni Ernawati

Beilstein J. Org. Chem. 2025, 21, 1031–1086, doi:10.3762/bjoc.21.85

• yield (Scheme 48B) [89]. Furthermore, Doris and co-workers (2019) also utilized a Au catalyst for oxidative esterification reactions. Herein, Au nanoparticles supported on carbon nanotubes (AuCNT) catalyzed the conversion of cinnamyl alcohol 157 to the corresponding ester 44 via hemiacetal-anchored on

Biobased carbon dots as photoreductants – an investigation by using triarylsulfonium salts

• Valentina Benazzi,
• Arianna Bini,
• Ilaria Bertuol,
• Mariangela Novello,
• Federica Baldi,
• Matteo Hoch,
• Alvise Perosa and
• Stefano Protti

Beilstein J. Org. Chem. 2025, 21, 1024–1030, doi:10.3762/bjoc.21.84

• ); triarylsulfonium salts; visible light; Introduction Carbon dots (CDs) are a class of zero-dimensional carbon-based semiconducting nanoparticles bearing on the surface a wide range of functional groups, such as carboxylic acids, alcohols, and amines, that garnered significant attention in the last decade among the

• typically exhibit excitation-dependent emission spectra and large Stokes shifts, features that are uncommon in traditional molecular fluorophores and semiconductor nanoparticles, and such behavior is attributed to the intrinsic heterogeneity of the CDs. The peculiar photophysics of carbon dots arises from

Formaldehyde surrogates in multicomponent reactions

• Cecilia I. Attorresi,
• Javier A. Ramírez and
• Bernhard Westermann

Beilstein J. Org. Chem. 2025, 21, 564–595, doi:10.3762/bjoc.21.45

• , 5 mol %) [63], indium (as In2O3 nanoparticles, 5 mol %) [64], iron (as FeCl3, 20 mol %) [65], cobalt (as CoBr2, 10 mol %) [66], and nickel (as Ni(py)4Cl2, 15 mol %) [67] can act as metal catalyst for the 3CC reaction. In all these cases, the temperature was lower (usually between 60–80 °C) compared

Beyond symmetric self-assembly and effective molarity: unlocking functional enzyme mimics with robust organic cages

• Keith G. Andrews

Beilstein J. Org. Chem. 2025, 21, 421–443, doi:10.3762/bjoc.21.30

• the past few years [20][70][235][315], and true organocatalysis is exceedingly rare [316]. Instead, catalytic systems tend to be composed of cavities that increase substrate solubility [317], or host nanoparticles [318][319][320][321][322][323][324][325][326], metals [44][327][328], photoactive groups

Red light excitation: illuminating photocatalysis in a new spectrum

• Lucas Fortier,
• Corentin Lefebvre and
• Norbert Hoffmann

Beilstein J. Org. Chem. 2025, 21, 296–326, doi:10.3762/bjoc.21.22

• of side reactions. This latter advantage has been notably exploited in the case of ring-closing olefin metathesis reactions, where Weizmann et al. utilized the photothermal response of plasmons from gold nanoparticles to activate the catalyst [17]. This approach contrasts with the work of Rovis et al

• thulium nanoparticles [26] and the use of a molybdenum-centered [27] and tungsten-centered complexes have been described in the literature [28]. The work by O. S. Wenger et al. introduces a system that mimics the Z-scheme of photosynthesis, utilizing a copper(I) bis(α-diimine) complex in combination with

• superoxide (O2•−) are simultaneously produced by the same photocatalytic system. In order to favor their combination leading to the peroxynitrite anion (ONOO−), the NO-releasing structure is incorporated in a polymeric structure 66 which generates micellar nanoparticles. The substituent R’ in the

Hot shape transformation: the role of PSar dehydration in stomatocyte morphogenesis

• Remi Peters,
• Levy A. Charleston,
• Karinan van Eck,
• Teun van Berlo and
• Daniela A. Wilson

Beilstein J. Org. Chem. 2025, 21, 47–54, doi:10.3762/bjoc.21.5

• is known to be able to self-assemble in a variety of structures, including micelles, vesicles, and nanoparticles [14][15]. However, the versatility of these polymers in shaping vesicles into asymmetric structures suitable for nanomotors remains relatively unexplored. While previous research has

Advances in radical peroxidation with hydroperoxides

• Oleg V. Bityukov,
• Pavel Yu. Serdyuchenko,
• Andrey S. Kirillov,
• Gennady I. Nikishin,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2024, 20, 2959–3006, doi:10.3762/bjoc.20.249

• ) [51]. The corresponding peroxides 30 are enough stable under the reaction conditions and were isolated in high yields (Scheme 12). Flow-modification of the 2-oxoindole peroxidation method using nanoparticles of iron oxide as the catalyst was proposed [52]. The summarized proposed reaction pathway is

Applications of microscopy and small angle scattering techniques for the characterisation of supramolecular gels

• Connor R. M. MacDonald and
• Emily R. Draper

Beilstein J. Org. Chem. 2024, 20, 2608–2634, doi:10.3762/bjoc.20.220

• accessed including dendritic structures; nanorods aggregated into fractal structures, disordered structures, as well as remaining discrete; and amorphous nanoparticles [89]. Similarly, a change in the solvent allowed a number of morphologies to be accessed (Figure 18), showing that characterisation of a

Machine learning-guided strategies for reaction conditions design and optimization

• Lung-Yi Chen and
• Yi-Pei Li

Beilstein J. Org. Chem. 2024, 20, 2476–2492, doi:10.3762/bjoc.20.212

• algorithm for the shell growth of core-shell semiconductor nanoparticles. This involves various unit operations such as phase separation, washing, and continuous in-situ spectral monitoring. Although the process conditions for this reaction system do not have as extensive a literature base for training data

Factors influencing the performance of organocatalysts immobilised on solid supports: A review

• Zsuzsanna Fehér,
• Dóra Richter,
• Gyula Dargó and
• József Kupai

Beilstein J. Org. Chem. 2024, 20, 2129–2142, doi:10.3762/bjoc.20.183

• lead to a decrease in selectivity. Connon and co-workers have attached a cinchona thiourea organocatalyst to magnetic nanoparticles 13 for the Michael addition of dimethyl malonate (10) to trans-β-nitrostyrene (11) (Scheme 3) [31]. To explore the potential impact of nanoparticles on catalyst efficiency

• , experiments were conducted. It was discovered that the nanoparticles themselves catalysed the formation of the racemic product in the absence of the thiourea catalyst. This finding elucidates the relatively poor enantioselectivity observed in reactions catalysed by the magnetic nanoparticle-supported

• organocatalyst. To validate this hypothesis, the Michael addition was repeated in the presence of both unsupported thiourea 14 and the nanoparticles. The resulting product was isolated with only 84% ee, indicating that the nanoparticles compete with the thiourea catalyst 14 for the substrate under these

Multicomponent syntheses of pyrazoles via (3 + 2)-cyclocondensation and (3 + 2)-cycloaddition key steps

• Ignaz Betcke,
• Alissa C. Götzinger,
• Maryna M. Kornet and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2024, 20, 2024–2077, doi:10.3762/bjoc.20.178

• solvents (DES) [83]. Catalysis can also be achieved using molecular iodine [84], AlCl3 [85], sodium ascorbate [86], and even solid-state and nanoparticle-mediated catalysts like CuO/ZrO2 [87], Fe3O4@Si@MoO2 [88], caspacin-cyclodextrin functionalized magnetite nanoparticles (CPS CD) [89], and Mg-Fe

The Groebke–Blackburn–Bienaymé reaction in its maturity: innovation and improvements since its 21st birthday (2019–2023)

• Cristina Martini,
• Muhammad Idham Darussalam Mardjan and
• Andrea Basso

Beilstein J. Org. Chem. 2024, 20, 1839–1879, doi:10.3762/bjoc.20.162

• aldehydic component has been generated in situ through Fe3O4-mediated aerobic oxidation of benzyl alcohols. Magnetic nanoparticles were supported by Shaabani and Farhid on spent coffee ground and served also as catalyst for the GBB reaction, although the role of coffee ground was not clearly explained [33

Electrocatalytic hydrogenation of cyanoarenes, nitroarenes, quinolines, and pyridines under mild conditions with a proton-exchange membrane reactor

• Koichi Mitsudo,
• Atsushi Osaki,
• Haruka Inoue,
• Eisuke Sato,
• Naoki Shida,
• Mahito Atobe and
• Seiji Suga

Beilstein J. Org. Chem. 2024, 20, 1560–1571, doi:10.3762/bjoc.20.139

• for a supporting electrolyte, which is necessary for conventional organic electrolysis, reduces the environmental impact, and facilitates product purification. In addition, using nanoparticles in the catalyst layer, which serve as the electrode, results in a large specific surface area and efficient

Synthesis and physical properties of tunable aryl alkyl ionic liquids based on 1-aryl-4,5-dimethylimidazolium cations

• Stefan Fritsch and
• Thomas Strassner

Beilstein J. Org. Chem. 2024, 20, 1278–1285, doi:10.3762/bjoc.20.110

• ionic liquid in addition to the possibility to introduce alkyl chains with varying length [30]. TAAILs have already been successfully used for the synthesis of nanoparticles and as solvents in catalysis [31][32]. Recently we have described the synthesis and physical properties of TAAILs which have been

Research progress on the pharmacological activity, biosynthetic pathways, and biosynthesis of crocins

• Zhongwei Hua,
• Nan Liu and
• Xiaohui Yan

Beilstein J. Org. Chem. 2024, 20, 741–752, doi:10.3762/bjoc.20.68

• , novel pharmaceutical systems, such as liposomes, microcapsules, and nanoparticles, were adopted to enhance the stability and bioavailability of these compounds [13][14][15]. To find a sustainable way of supplying crocins, researchers have developed various approaches to produce them, including plant

Evaluation of the enantioselectivity of new chiral ligands based on imidazolidin-4-one derivatives

• Jan Bartáček,
• Karel Chlumský,
• Jan Mrkvička,
• Lucie Paloušová,
• Miloš Sedlák and
• Pavel Drabina

Beilstein J. Org. Chem. 2024, 20, 684–691, doi:10.3762/bjoc.20.62

• catalytic arrangements of the most enantioselective catalysts, including anchoring on polystyrene beads [8][9], magnetic nanoparticles [10], or block copolymers composed of PEG-poly(Glu) [11]. These modifications have facilitated the recycling of the catalysts, offering numerous advantages, including

Green and sustainable approaches for the Friedel–Crafts reaction between aldehydes and indoles

• Periklis X. Kolagkis,
• Eirini M. Galathri and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2024, 20, 379–426, doi:10.3762/bjoc.20.36

• [96]. Nanocatalysis Nanocatalysis has emerged over the last decades as a sustainable and green field of organic catalysis that offers unparalleled opportunities for chemical transformations that were previously deemed unfeasible. The use of nanoparticles, compounds with a cross section of less than

• , Rahimizadeh et al. proposed the use of the nanometal oxide TiO2, which was already reported as an effective nanocatalyst for the promotion of various organic transformations [100]. TiO2 nanoparticles are non-toxic, inexpensive and reusable compounds that are synthesized through a sol–gel method. This method

• of Fe3O4 nanoparticles (Scheme 15) [101][102]. This organic–inorganic hybrid material was synthesized by the immobilization of the dodecatungstovanadophosphoric acid (HPA) on TPI-Fe3O4 with N-[3-(triethoxysilyl)propyl]isonicotinamide (TPI), acting as the linker for the heterogeneous catalyst, while

Mechanisms for radical reactions initiating from N-hydroxyphthalimide esters

• Carlos R. Azpilcueta-Nicolas and
• Jean-Philip Lumb

Beilstein J. Org. Chem. 2024, 20, 346–378, doi:10.3762/bjoc.20.35

• formation of silver nanoparticles (AgNP) on the cathode's surface [116] (Scheme 35B). The use of this Ag-doped cathode led to slower mass transport and minimized side reactions caused by rapid reduction of RAEs, thereby avoiding substrate decomposition and enhancing reaction yields (Scheme 35B). Furthermore

Perspectives on push–pull chromophores derived from click-type [2 + 2] cycloaddition–retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes

• Michio Yamada

Beilstein J. Org. Chem. 2024, 20, 125–154, doi:10.3762/bjoc.20.13

• wormlike nanoparticles. In rotaxanes, the utilization of metal–ligand bonding involving CuI is a common strategy for immobilizing a thread moiety within a macrocycle. However, the efficacy of such a bonding is compromised when catalysts are used in stoppering reactions, e.g., the copper-catalyzed azide

Photoinduced in situ generation of DNA-targeting ligands: DNA-binding and DNA-photodamaging properties of benzo[c]quinolizinium ions

• Julika Schlosser,
• Olga Fedorova,
• Yuri Fedorov and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 101–117, doi:10.3762/bjoc.20.11

• -based nanoparticles [58][59]. But although these classes of compounds have been intensively studied and already contributed significantly to the field of PDT, there is still a demand for novel DNA-photodamaging ligands that could be applied for specific purposes, e.g., to improve efficacy or to limit

Facile access to pyridinium-based bent aromatic amphiphiles: nonionic surface modification of nanocarbons in water

• Lorenzo Catti,
• Shinji Aoyama and
• Michito Yoshizawa

Beilstein J. Org. Chem. 2024, 20, 32–40, doi:10.3762/bjoc.20.5

• surface properties of the aromatic micelles (PA-R)n and their host–guest composites including nanocarbons in water. The ZP of self-assembled nanoparticles evaluates their structural stability in solution against aggregation through electrostatic repulsion [25]. Solutions of the micelles in Milli-Q water

Aldiminium and 1,2,3-triazolium dithiocarboxylate zwitterions derived from cyclic (alkyl)(amino) and mesoionic carbenes

• Nedra Touj,
• François Mazars,
• Guillermo Zaragoza and
• Lionel Delaude

Beilstein J. Org. Chem. 2023, 19, 1947–1956, doi:10.3762/bjoc.19.145

• featuring monodentate [44][45], chelating bidentate [46][47][48][49][50][51][52][53][54][55], or bridging bidentate NHC·CS2 ligands [45][51][52]. Small bimetallic clusters [51][52][56], coordination polymers [57], self-assembled monolayers [58], and nanoparticles [45] based on these zwitterions were also