The effect of neighbouring group participation and possible long range remote group participation in O-glycosylation

• Rituparna Das and
• Balaram Mukhopadhyay

Beilstein J. Org. Chem. 2025, 21, 369–406, doi:10.3762/bjoc.21.27

• inversion in carbohydrates was illustrated extensively by Frush and Isbell [75] with silver carbonate as the promoter, drawing analogy with an SN2-type substitution mechanism with the formation of the acetoxonium ion intermediate [76]. An acyl protecting group in the vicinal C-2 position is widely accepted

Streamlined modular synthesis of saframycin substructure via copper-catalyzed three-component assembly and gold-promoted 6-endo cyclization

• Asahi Kanno,
• Ryo Tanifuji,
• Satoshi Yoshida,
• Sota Sato,
• Saori Maki-Yonekura,
• Kiyofumi Takaba,
• Jungmin Kang,
• Kensuke Tono,
• Koji Yonekura and
• Hiroki Oguri

Beilstein J. Org. Chem. 2025, 21, 226–233, doi:10.3762/bjoc.21.14

• gold complex and the silver salt, to efficiently achieve the 6-endo cyclization and subsequent conversions. During the development of this cascade synthesis process, we serendipitously discovered the involvement of a sky-blue fluorescent transient intermediate 18 (Figure 2). We therefore investigated

Hypervalent iodine-mediated intramolecular alkene halocyclisation

• Charu Bansal,
• Oliver Ruggles,
• Albert C. Rowett and
• Alastair J. J. Lennox

Beilstein J. Org. Chem. 2024, 20, 3113–3133, doi:10.3762/bjoc.20.258

• instead proceeded with addition of dichloro(pyridine-2-carboxylato)gold(III) complex in combination with silver triflimide, AgNTf2. A range of β-fluoroazepanes 7 were successfully synthesised with high enantiomeric purity in good yields. A mechanism for the synthesis of β-fluorinated piperidines was

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

Synthesis of pyrrole-fused dibenzoxazepine/dibenzothiazepine/triazolobenzodiazepine derivatives via isocyanide-based multicomponent reactions

• Marzieh Norouzi,
• Mohammad Taghi Nazeri,
• Ahmad Shaabani and
• Behrouz Notash

Beilstein J. Org. Chem. 2024, 20, 2870–2882, doi:10.3762/bjoc.20.241

• respiratory tract. Which leads to skin and eye irritation, blurred vision, dizziness, weakness/fatigue, hypotension, seizures, and respiratory failure. The following instructions are required to work with TMSN3. It is necessary to have a silver shield apron, breathing mask, safety glasses, lab coat, and

N-Glycosides of indigo, indirubin, and isoindigo: blue, red, and yellow sugars and their cancerostatic activity

• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 2840–2869, doi:10.3762/bjoc.20.240

• protective groups had to be employed. The reaction of the 3-iodoindoles β-28a and β-28b with an excess of silver acetate under mild acidic conditions afforded 3-acetoxyindol-N-rhamnosides β-29a and β-29b, respectively. The application of the conditions used for the synthesis of indirubin-N-glycoside 17a

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

• analysis [8]. Silver nitrate column chromatography: Silver nitrate column chromatography was carried out as described [45]. An aq solution of silver nitrate (5.5 g) in H2O (30 mL) was added to silica gel (50 g). Water was added to barely cover the silica gel. The silica was stirred with a glass rod and

• pentane and diethyl ether (100:2) and obtained as a 1:1 mixture of diastereomers. This was followed by silver nitrate column chromatography using pentane and ethyl acetate (97.5:2.5) to enrich one diastereomer (de(E) = 50%). The NMR data were in agreement with published values [31]. Colorless oil: 15 mg

Efficacy of radical reactions of isocyanides with heteroatom radicals in organic synthesis

• Akiya Ogawa and
• Yuki Yamamoto

Beilstein J. Org. Chem. 2024, 20, 2114–2128, doi:10.3762/bjoc.20.182

• phenanthridines via silver-catalyzed radical sulfonylation–cyclization of 2-isocyanobiphenyls (Scheme 25) [98]. Wang et al. reported a radical borylative cyclization of 2-isocyanobiaryls with N-heterocyclic carbene borane (Scheme 26) [99]. The boryl radical generated via hydrogen abstraction in the presence of di

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

Solvent-dependent chemoselective synthesis of different isoquinolinones mediated by the hypervalent iodine(III) reagent PISA

• Ze-Nan Hu,
• Yan-Hui Wang,
• Jia-Bing Wu,
• Ze Chen,
• Dou Hong and
• Chi Zhang

Beilstein J. Org. Chem. 2024, 20, 1914–1921, doi:10.3762/bjoc.20.167

• metal reagents, including cobalt [10], copper [11], rhodium [12][13][14], palladium [15][16][17], silver [18], and gold [19] catalysts, have been reported. However, compared to the widespread use of metal catalysts, the synthesis of isoquinolinone scaffolds mediated by environmentally friendly

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

• on different substrates, the conditions were similar: 20 mol % of the catalyst, ethanol as solvent at 80 °C in the first case, 30 mol % of catalyst, ethylene glycol at 90 °C in the second case; however, a striking difference appears when the reaction was carried out in the absence of silver catalyst

• of chalcogen-based noncovalent organocatalysts. In 2023, Bolotin et al. published another article on the same subject [15], reporting a general improvement of electrophilic activation of carbonyl and imino groups by synergetic effect of aryl iodonium salts and silver cations. However, when similar

Syntheses and medicinal chemistry of spiro heterocyclic steroids

• Laura L. Romero-Hernández,
• Ana Isabel Ahuja-Casarín,
• Penélope Merino-Montiel,
• Sara Montiel-Smith,
• José Luis Vega-Báez and
• Jesús Sandoval-Ramírez

Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152

• tolylhydrazonoyl chloride derivative 54 [35]. The reaction conducted in the presence of silver acetate at room temperature, achieved yields of 78–81% of the 16-spiropyrazolines 55a,b (Scheme 17). 6-Spiroimidazoline steroids In 2015, Dar’s group reported a small library of spiroimidazo[1,2-a]pyridines obtained

Supramolecular assemblies of amphiphilic donor–acceptor Stenhouse adducts as macroscopic soft scaffolds

• Ka-Lung Hung,
• Leong-Hung Cheung,
• Yikun Ren,
• Ming-Hin Chau,
• Yan-Yi Lam,
• Takashi Kajitani and
• Franco King-Chi Leung

Beilstein J. Org. Chem. 2024, 20, 1590–1603, doi:10.3762/bjoc.20.142

• Rigaku NANOPIX equipped with a HyPix-6000 (Rigaku) detector. The scattering vector (q = 4⋅π⋅sin(θ)/λ), scattering angle θ, and the position of the incident X-ray beam on the detectors were calibrated using several orders of layer reflections from silver behenate (d = 58.380 Å), where λ refers to the

Benzylic C(sp³)–H fluorination

• Alexander P. Atkins,
• Alice C. Dean and
• Alastair J. J. Lennox

Beilstein J. Org. Chem. 2024, 20, 1527–1547, doi:10.3762/bjoc.20.137

• selective for primary benzylic fluorination (11) and secondary benzylic fluorination (12) in the presence of tertiary benzylic sites. Although no mechanism has been proposed, the authors concluded it likely proceeded via a radical pathway [23]. In 2017, Baxter and co-workers introduced a silver-catalysed

• substituents on the aryl group benefitted from fewer HF equivalents and the addition of silver fluoride. A follow-up report showed that only minor alterations to the conditions were needed to make the process amenable to the use of [18F]KF, facilitating radiofluorination [81]. Both reports used hypervalent

• , non-photochemical, silver-catalysed HAT radical-polar crossover mechanism for nucleophilic benzylic fluorination (Figure 34) [85]. The authors proposed a similar mechanistic pathway to the photochemical methods, citing the use of amide ligands as important for modulating the silver catalyst stability

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

• ). The setup consisted of a glassy carbon working electrode, a platinum wire counter electrode and a silver wire as reference electrode. The cutoff at which the cathodic limit Ered and the anodic limit Eox were determined was −0.1 and 0.1 mA cm−2. The electro-chemical window EEW is determined from the

Auxiliary strategy for the general and practical synthesis of diaryliodonium(III) salts with diverse organocarboxylate counterions

• Naoki Miyamoto,
• Daichi Koseki,
• Kohei Sumida,
• Elghareeb E. Elboray,
• Naoko Takenaga,
• Ravi Kumar and
• Toshifumi Dohi

Beilstein J. Org. Chem. 2024, 20, 1020–1028, doi:10.3762/bjoc.20.90

• compared to trifluoroacetic acid, TfOH, HBF4, and p-TsOH, present a wider substrate scope, including acid-sensitive groups, in the preparation of diaryliodonium(III) salts. While the counterion exchange of diaryliodonium(III) chloride with silver acetate was reported [20], this method required heating

(Bio)isosteres of ortho- and meta-substituted benzenes

• H. Erik Diepers and
• Johannes C. L. Walker

Beilstein J. Org. Chem. 2024, 20, 859–890, doi:10.3762/bjoc.20.78

• larger than in meta-benzene, the dihedral angle θ is significantly larger and strongly dependent on the specific substituents. 1,3-Cuneanes can be obtained by metal-induced isomerisation of 1,4-cubanes [69]. Recent reports of their synthesis indicate that silver salts enable the isomerisation to occur

Switchable molecular tweezers: design and applications

• Pablo Msellem,
• Maksym Dekthiarenko,
• Nihal Hadj Seyd and
• Guillaume Vives

Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45

Ligand effects, solvent cooperation, and large kinetic solvent deuterium isotope effects in gold(I)-catalyzed intramolecular alkene hydroamination

• Ruichen Lan,
• Brock Yager,
• Yoonsun Jee,
• Cynthia S. Day and
• Amanda C. Jones

Beilstein J. Org. Chem. 2024, 20, 479–496, doi:10.3762/bjoc.20.43

• , precluding the need to use silver salts to generate a cationic catalyst with a weakly coordinating anion [64]. It is increasingly being tested as an additive in gold reactions, sometimes to beneficial effect [65], sometimes to neutral effect [22]. We are somewhat surprised by the detrimental effects seen

Synthesis of 2,2-difluoro-1,3-diketone and 2,2-difluoro-1,3-ketoester derivatives using fluorine gas

• Alexander S. Hampton,
• David R. W. Hodgson,
• Graham McDougald,
• Linhua Wang and
• Graham Sandford

Beilstein J. Org. Chem. 2024, 20, 460–469, doi:10.3762/bjoc.20.41

• of gem-dihalo groups to corresponding CF2 derivatives using silver tetrafluoroborate [5] or mercury(II) fluoride [6], deoxyfluorination of carbonyl derivatives using diethylaminosulfur trifluoride (DAST) or related Deoxo-Fluor and Xtalfluor reagents [7][8]. Alternatively, oxidative

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

• -halides [115]. Their optimized reaction conditions required a NiII precursor, 2,2’-bipyridine (bpy) as ligand, silver nitrate (AgNO3) as an additive and the combination of a magnesium (Mg) sacrificial anode and a RVC cathode (Scheme 35A). A crucial discovery in advancing this methodology was the in situ

• 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

Synthesis of the 3’-O-sulfated TF antigen with a TEG-N₃ linker for glycodendrimersomes preparation to study lectin binding

• Mark Reihill,
• Hanyue Ma,
• Dennis Bengtsson and
• Stefan Oscarson

Beilstein J. Org. Chem. 2024, 20, 173–180, doi:10.3762/bjoc.20.17

• 1 have recently been reported, one using an enzymatic approach and a commercial α-TEG-N3 GalNAc acceptor [9] and one using glycosyl bromide donors and silver salt-promoted glycosylations [10]. Results and Discussion To introduce the 2-[2-(2-chloroethoxy)ethoxy]ethyl (TEG-Cl) spacer both a Fischer

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

Multi-redox indenofluorene chromophores incorporating dithiafulvene donor and ene/enediyne acceptor units

• Christina Schøttler,
• Kasper Lund-Rasmussen,
• Line Broløs,
• Philip Vinterberg,
• Ema Bazikova,
• Viktor B. R. Pedersen and
• Mogens Brøndsted Nielsen

Beilstein J. Org. Chem. 2024, 20, 59–73, doi:10.3762/bjoc.20.8

• obtained using an Autolab PGSTAT12 instrument and Nova 1.11 software with a scan rate of 0.1 V/s for the CVs. A silver wire immersed in a 0.1 M Bu4NPF6 solution in CH2Cl2 separated from the analyte solution by a frit was used as the reference electrode, a Pt wire was used as the counter electrode, and a

Synthesis of N-acyl carbazoles, phenoxazines and acridines from cyclic diaryliodonium salts

• Nils Clamor,
• Mattis Damrath,
• Thomas J. Kuczmera,
• Daniel Duvinage and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2024, 20, 12–16, doi:10.3762/bjoc.20.2

• turnover of the desired reaction [35]. To mitigate this, using silver salts as iodide scavengers in the reaction was attempted but yielded none of the desired product (Table 1, entry 2). DMF as a solvent lowered the yield to 16% (Table 1, entry 3). Switching the catalyst system to Cu(OTf)2/glyme gave a