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

• mixtures of ring sizes, either by enzymatic synthesis (cyclodextrins) or thermodynamic synthesis, and are used after separation of the different ring sizes. Since the macrocycles are generically hydrophobic on the interior, they can perform catalysis by dual-confinement of two hydrophobic substrates from

• purification possibilities available for robust organic cages mean access to structural families via stepwise synthesis or statistical methods followed by separation is facile, as demonstrated by Otte [42][43][44] and ourselves [41]. The lack of internal functionality in cavities doesn’t just reduce the

Identification and removal of a cryptic impurity in pomalidomide-PEG based PROTAC

• Bingnan Wang,
• Yong Lu and
• Chuo Chen

Beilstein J. Org. Chem. 2025, 21, 407–411, doi:10.3762/bjoc.21.28

• product on HPLC even for the reaction of diethylene glycolamine and 1. Capping the free hydroxy group with a methyl group improved the separation on HPLC marginally. However, incorporating a clickable propargyl group greatly benefited separation. Similar to the alcohol, amino-PEG5-acid also reacted with 1

• enable an easy separation of the byproduct. Pleasingly, reacting the mixture of 3 and 6 with taurine converted 6 to sulfonate 10 (Scheme 2) that can be removed by a simple aqueous wash with sodium bicarbonate. Whereas taurine may also react with 3, the overall yield of 3 was not affected significantly

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

• have been proven to be efficient in photoredox catalysis [9][10][11][12]. Actually, MLCT enables a charge separation for which the ligand-based electron can trigger a chemical reduction while the metal-centered hole, a chemical oxidation. This type of excitation is particularly enhanced in heavy metals

Hydrogen-bonded macrocycle-mediated dimerization for orthogonal supramolecular polymerization

• Wentao Yu,
• Zhiyao Yang,
• Chengkan Yu,
• Xiaowei Li and
• Lihua Yuan

Beilstein J. Org. Chem. 2025, 21, 179–188, doi:10.3762/bjoc.21.10

• noncovalent bonding interactions. It also confers on supramolecular assemblies with higher complexity and multilevel ordering [9][10][11], leading to a vast number of applications, for example, for use in detection and separation [12], sensing [13], photocatalysis [14], release [15], and as thermochromic and

Recent advances in organocatalytic atroposelective reactions

• Henrich Szabados and
• Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6

• 50 °C in isopropanol just after a couple of hours. The racemization barriers of the products were only slightly higher (28 kcal/mol) than the minimal requirement for separation of atropoisomers (24 kcal/mol). Scale-up done on the one-mmol-scale provided the corresponding product in comparable yields

Facile one-pot reduction of β-nitrostyrenes to phenethylamines using sodium borohydride and copper(II) chloride

• Laura D’Andrea and
• Simon Jademyr

Beilstein J. Org. Chem. 2025, 21, 39–46, doi:10.3762/bjoc.21.4

• atmosphere, special precautions, and with isolated yields up to 60% [14][15]. Due to the formation of side products, final purification of the amino derivatives requires the use of either multiple separation techniques, chromatography, or distillation [15][16][17][18] (Scheme 1). Differently from lithium

• extraction process and copper(II) removal. However, the addition of DETA led to decreased yields and a deterioration of the phase separation. It was observed that using a 20% aqueous sodium hydroxide solution, instead of 35%, negatively impacted phase separation, making the extraction process more time

• ). UPLC-MS analyses were performed on a Waters Acquity H-class UPLC with a Sample Manager FTN and a TUV dual wavelength detector coupled to a QDa single quadrupole analyzer using electrospray ionization (ESI). UPLC separation was achieved with a C18 reversed-phase column (Acquity UPLC BEH C18, 2.1 mm × 50

Emerging trends in the optimization of organic synthesis through high-throughput tools and machine learning

• Pablo Quijano Velasco,
• Kedar Hippalgaonkar and
• Balamurugan Ramalingam

Beilstein J. Org. Chem. 2025, 21, 10–38, doi:10.3762/bjoc.21.3

• , stirring, heating, and cooling modules for enhanced versatility. In addition, the platform is capable of performing under inert and low-pressure atmospheres, handling separation steps, and pressure sensing for reaction monitoring. Its efficacy and robustness were confirmed through the successful synthesis

• , differing from established isolation and separation techniques, holds the promise of not only enhancing the efficiency of HTE flow synthesis but also paving the way for more sustainable growth in this research area. Autonomous self-optimizing flow reactors Autonomous self-optimizing flow reactors (ASFRs

Synthesis, characterization, and photophysical properties of novel 9‑phenyl-9-phosphafluorene oxide derivatives

• Shuxian Qiu,
• Duan Dong,
• Jiahui Li,
• Huiting Wen,
• Jinpeng Li,
• Yu Yang,
• Shengxian Zhai and
• Xingyuan Gao

Beilstein J. Org. Chem. 2024, 20, 3299–3305, doi:10.3762/bjoc.20.274

• recent years, and they are mostly based on purely organic electron donor−electron acceptor (D−A) or D−A−D systems with significant intramolecular charge transfer interactions for frontier molecular orbital separation [28][29][30]. Due to the electron-accepting properties, PhFlOP can clearly act as an

Ceratinadin G, a new psammaplysin derivative possessing a cyano group from a sponge of the genus Pseudoceratina

• Shin-ichiro Kurimoto,
• Kouta Inoue,
• Taito Ohno and
• Takaaki Kubota

Beilstein J. Org. Chem. 2024, 20, 3215–3220, doi:10.3762/bjoc.20.267

• ), as well as additional signals not matching those of any known psammaplysin derivatives. Further separation of this fraction using C18 HPLC led to the isolation of ceratinadin G (1, 0.4 mg, 3.2 × 10−4%) along with psammaplysin F (2) [10][11][12]. Ceratinadin G (1) was isolated as an optically active

Discovery of ianthelliformisamines D–G from the sponge Suberea ianthelliformis and the total synthesis of ianthelliformisamine D

• Sasha Hayes,
• Yaoying Lu,
• Bernd H. A. Rehm and
• Rohan A. Davis

Beilstein J. Org. Chem. 2024, 20, 3205–3214, doi:10.3762/bjoc.20.266

• -bonded silica (≈1 g), packed into a stainless-steel guard cartridge, and subjected to phenyl semipreparative RP-HPLC separation. Isocratic conditions of 90% H2O (0.1% TFA)/10% MeOH (0.1% TFA) were initially employed for the first 10 min, then a linear gradient to 100% MeOH (0.1% TFA) was run over 40 min

Advances in the use of metal-free tetrapyrrolic macrocycles as catalysts

• Mandeep K. Chahal

Beilstein J. Org. Chem. 2024, 20, 3085–3112, doi:10.3762/bjoc.20.257

• and separation technology [3][4][5][6][7][8]. Conversely, porphyrins are connected via methine (=CH-) bridges, resulting in an 18 π-electron macrocyclic system affording macrocyclic planarity as well as unique photophysical and electrochemical properties (Figure 1b). While corroles share similarities

• optically active form with 16.7% ee for 63a and 11.8% ee for 63b, respectively (Table 4). The pH-induced aggregation does not only enable to control the catalytic activity, but it also allows a straightforward separation and recovery of the catalyst from the reaction mixture by acidification and

Enantioselective regiospecific addition of propargyltrichlorosilane to aldehydes catalyzed by biisoquinoline N,N’-dioxide

• Noble Brako,
• Sreerag Moorkkannur Narayanan,
• Amber Burns,
• Layla Auter,
• Valentino Cesiliano,
• Rajeev Prabhakar and
• Norito Takenaka

Beilstein J. Org. Chem. 2024, 20, 3069–3076, doi:10.3762/bjoc.20.255

• ][15][16][17][18][19], the separation of which is by no means trivial [20] (Scheme 1). Nonetheless, substituents at the carbon atom indicated by γ (R2) of these reagents have been shown to bias the metallotropic rearrangement and/or the kinetic reactivity of the competing regioisomeric intermediates

Extension of the π-system of monoaryl-substituted norbornadienes with acetylene bridges: influence on the photochemical conversion and storage of light energy

• Robin Schulte,
• Dustin Schade,
• Thomas Paululat,
• Till J. B. Zähringer,
• Christoph Kerzig and
• Heiko Ihmels

Beilstein J. Org. Chem. 2024, 20, 3061–3068, doi:10.3762/bjoc.20.254

• because by-products interfered with the chromatographic separation; however, these yields are similar to the ones reported for resembling norbornadienes [34][37]. The novel compounds 1h–l,n were identified and fully characterized by NMR spectroscopy (1H, 13C, COSY, HSQC, HMBC), melting point, and

4,6-Diaryl-5,5-difluoro-1,3-dioxanes as chiral dopants for liquid crystal compositions

• Maurice Médebielle,
• Peer Kirsch,
• Jérémy Merad,
• Carolina von Essen,
• Clemens Kühn and
• Andreas Ruhl

Beilstein J. Org. Chem. 2024, 20, 2940–2945, doi:10.3762/bjoc.20.246

• here preliminary results with the diastereoselective synthesis of two 4,6-diphenyl-5,5-difluoro-1,3-dioxanes (rac-3 and rac-4) and their separation into their corresponding enantiomers ((R,R)-3 and (S,S)-3; (R,R)-4 and (S,S)-4). rac-3 and rac-4 are obtained from readily available racemic 2,2-difluoro

C–C Coupling in sterically demanding porphyrin environments

• Liam Cribbin,
• Brendan Twamley,
• Nicolae Buga,
• John E. O’ Brien,
• Raphael Bühler,
• Roland A. Fischer and
• Mathias O. Senge

Beilstein J. Org. Chem. 2024, 20, 2784–2798, doi:10.3762/bjoc.20.234

• previously, enrichment to the αβαβ, isomer may be necessary to remove the impact of opposing bromine atoms on the coupling reaction. Separation of the four individual atropisomers (αβαβ, α2β2, α3β, α4) has been accomplished before in dodecasubstituted porphyrins through Ni(II) metalation [15]. The core

• metalation effect prevents inner core N–H tautomerism [64] and thus increases the structural symmetry of the macrocycle [65][66], leading to more facile atropisomeric separation. However, in the case of compound 11 the atropisomers could not be separated due to low rotational barriers and similar polarities

• , even with Ni(II) metalation. There are many other methods available to achieve different desired atropisomeric ratios. These include thermal enrichment [67][68], photoracemization [69][70], axial-ligand coordination [71], precise separation techniques [50] or a combination of the procedures mentioned

Interaction of a pyrene derivative with cationic [60]fullerene in phospholipid membranes and its effects on photodynamic actions

• Hayato Takagi,
• Çetin Çelik,
• Ryosuke Fukuda,
• Qi Guo,
• Tomohiro Higashino,
• Hiroshi Imahori,
• Yoko Yamakoshi and
• Tatsuya Murakami

Beilstein J. Org. Chem. 2024, 20, 2732–2738, doi:10.3762/bjoc.20.231

• an acceptor in photoinduced charge-separation systems, we have previously employed ferrocene-porphyrin-C60 triad molecules (Figure 1a) in a biological system to control the plasma membrane potential (Vm) of living mammalian neuronal cells under photoirradiation [4][5][6]. Generally, Vm originates

Synthesis of benzo[f]quinazoline-1,3(2H,4H)-diones

• Ruben Manuel Figueira de Abreu,
• Peter Ehlers and
• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 2708–2719, doi:10.3762/bjoc.20.228

• attempt, we used platinum(II) chloride (PtCl2) as the Lewis acid and 4a as the model starting material. The reaction afforded a mixture of the desired product 5a and the starting material. Separation of both compounds proved to be difficult and, hence, optimisation was carried out as depicted in Table 1

The scent gland composition of the Mangshan pit viper, Protobothrops mangshanensis

• Jonas Holste,
• Paul Weldon,
• Donald Boyer and
• Stefan Schulz

Beilstein J. Org. Chem. 2024, 20, 2644–2654, doi:10.3762/bjoc.20.222

• diastereomers were then subjected to silver nitrate column chromatography to separate the geometric isomers. This separation was only partially achieved (Supporting Information File 1, Figure S10), but one diastereomer was enriched and the sample was subjected to NOESY NMR experiments. Coupling was observed

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

• could CLSM observe the initial kinetic self-sorting of gelators, but it also showed that the homogenous mixture of NFs and CFs can undergo a higher level of self-sorting, resulting in macroscopic phase separation (Figure 4). To gather a three-dimensional surface profile of a material, AFM utilises a

Visible-light-mediated flow protocol for Achmatowicz rearrangement

• Joachyutharayalu Oja,
• Sanjeev Kumar and
• Srihari Pabbaraja

Beilstein J. Org. Chem. 2024, 20, 2493–2499, doi:10.3762/bjoc.20.213

• transformations, then reaction extraction and separation, into a single process, which are typically performed individually/separately in batch methods. This enhances the overall efficiency for obtaining the desired product(s) from the reaction mixture. In continuation to our efforts on developing flow-based

• (see details in Supporting Information File 1, Table S2). In this context, our previously in-house-developed liquid–liquid extractor was utilized (see details in Supporting Information File 1, Figure S4) [27]. After few trials towards optimization of extraction and separation, the best yield (82%) was

• obtained when EtOAc (flow rate set at 2.5 mL/min), water (flow rate set at 4.5 mL/min) were taken with the extraction time of 0.25 min and separation time of 0.11 min (see details in Supporting Information File 1, Table S2, entry 5). To verify the steadiness of the newly constructed integrated photo-flow

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

• interdependencies between different reaction sequences, such as additional separation and purification steps, could reduce the overall yield [202]. This indicates that the suboptimal combination of each reaction does not necessarily represent the global optimum for multistep synthesis [203][204][205]. In contrast

• 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

Facile preparation of fluorine-containing 2,3-epoxypropanoates and their epoxy ring-opening reactions with various nucleophiles

• Yutaro Miyashita,
• Sae Someya,
• Tomoko Kawasaki-Takasuka,
• Tomohiro Agou and
• Takashi Yamazaki

Beilstein J. Org. Chem. 2024, 20, 2421–2433, doi:10.3762/bjoc.20.206

• during the lactone-forming process. Their close structural resemblance led to a significant peak overlap both in the 1H and 19F NMR spectra which made it difficult to obtain their exact ratio and thus, the combined 19F NMR yields were shown in Table 4. Separation of these two compounds was eventually

Improved deconvolution of natural products’ protein targets using diagnostic ions from chemical proteomics linkers

• Andreas Wiest and
• Pavel Kielkowski

Beilstein J. Org. Chem. 2024, 20, 2323–2341, doi:10.3762/bjoc.20.199

• . Acquisition techniques benefit from possible multistage ion separation and isolation, and diverse fragmentation techniques. All of that is nowadays combined in one instrument to provide greater flexibility of the spectra acquisition setup [7][8][9][10][11][12][13][14][15][16]. Given the sheer amount of data

• proteins can be proteolytically cleaved on-beads or directly eluted for further enrichment on an affinity resin. Due to the easy handling of the magnetic beads and separation for the liquid phase using the magnet, the protocol utilizing the carboxylate magnetic beads was first developed for whole proteome

Electrochemical allylations in a deep eutectic solvent

• Sophia Taylor and
• Scott T. Handy

Beilstein J. Org. Chem. 2024, 20, 2217–2224, doi:10.3762/bjoc.20.189

• partial solubility of ethylene glycol in methoxycyclopentane as ethylene glycol could be clearly seen in the 1H NMR spectrum of the crude reaction extracts. It should also be noted that the lower isolated yields most likely reflect mechanical losses during extraction and chromatographic separation as the

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

• ] reactions. POFs [102] are hydrocarbon systems that contain pores, of which COFs are a subgroup. POFs are widely applied in the fields of gas adsorption and storage, the separation of gases, catalysis, energy storage, photocatalysis, etc., and have many different types, such as hyper-cross-linked polymers