Unprecedented synthesis of a 14-membered hexaazamacrocycle

• Anastasia A. Fesenko and
• Anatoly D. Shutalev

Beilstein J. Org. Chem. 2023, 19, 1728–1740, doi:10.3762/bjoc.19.126

• calculations was proposed. It involves nucleophilic attack of hydrazine on the C2 carbon of the pyrimidine ring followed by cleavage of the C2–N3 bond, dimerization of the bis-amidrazone formed, and macrocyclization of the dimer. The DFT calculations also showed that the hydrazine-promoted transformation of

Benzoimidazolium-derived dimeric and hydride n-dopants for organic electron-transport materials: impact of substitution on structures, electrochemistry, and reactivity

• Swagat K. Mohapatra,
• Khaled Al Kurdi,
• Samik Jhulki,
• Georgii Bogdanov,
• John Bacsa,
• Maxwell Conte,
• Tatiana V. Timofeeva,
• Seth R. Marder and
• Stephen Barlow

Beilstein J. Org. Chem. 2023, 19, 1651–1663, doi:10.3762/bjoc.19.121

• stable DMBI+ (1+) species, a hydrogen atom must be lost from the dopant, in some cases resulting in the incorporation of hydrogen-reduced side products into the semiconductor film [9], although in other cases it may be lost as H2 [8][10][11]. The first report of a (DMBI)2 dimer (12, Figure 1) was of 1a2

• more soluble than the iodides in THF, so were reductively dimerized to 12 in THF using Na:Hg, although reduction of 1i+PF6− failed to afford 1i2. As we have noted before for other 12 species, amides (V, Scheme 1) are encountered as both byproducts of dimer synthesis and dimer decomposition products [14

• molecular C2 symmetry, while the Y–C–C–Y torsion angles for 1h2 and 1e2 are 149.4° and 140.3°, respectively, and thus both intermediate between the perfectly staggered (180° torsion) and neighboring eclipsed conformation (120°). The imidazole rings in the previously reported and present dimer structures are

Tying a knot between crown ethers and porphyrins

• Maksym Matviyishyn and
• Bartosz Szyszko

Beilstein J. Org. Chem. 2023, 19, 1630–1650, doi:10.3762/bjoc.19.120

• to a dimer 37 was achieved using N,N-dimethylformamide, dimethyl sulfoxide, or acetonitrile. Interestingly, the dissolution of compound 37 in CHCl3, MeOH, or EtOH resulted in the interconversion to 36 within 1–2 days, as evidenced by 1H NMR spectroscopy. The Ravikanth group has developed an

• applications. Porphyrin and crown ether. Timeline demonstrating the contributions into the crown ether–porphyrin chemistry. Tetra-crowned porphyrin 1 and dimer 2 formed upon K+ binding. meso-Crowned 25-oxasmaragdyrins 3a–c and their boron(III) complexes (3a–c)-BF2. CsF ion pair binding by 5. The molecular

A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics

• Kathryn M. Wolfe,
• Shahidul Alam,
• Eva German,
• Fahad N. Alduayji,
• Maryam Alqurashi,
• Frédéric Laquai and
• Gregory C. Welch

Beilstein J. Org. Chem. 2023, 19, 1620–1629, doi:10.3762/bjoc.19.119

• the CILs PDIN-FB, PDIN-B, CN-PDIN-FB, and CN-PDIN-B. Evolution of the dimer tPDI2N-R [23] as an NFA to PDIN-B/PDIN-FB monomers to serve as CILs, where the addition of nitrile functional group on the monomeric PDIN-B/PDIN-FB materials serve to stabilize FMOs. a) Structures of PDIN-FB, PDIN-B, CN-PDIN

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

• action of laccase enzymes [5]. The radical then rearranges to form a semiquinone radical and reacts rapidly with a neighboring urushiol molecule to produce a biphenyl dimer. The dimers further polymerize to form the polymer [8]. Radical processes also occur in oceans. The mussel attachment system

Enabling artificial photosynthesis systems with molecular recycling: A review of photo- and electrochemical methods for regenerating organic sacrificial electron donors

• Grace A. Lowe

Beilstein J. Org. Chem. 2023, 19, 1198–1215, doi:10.3762/bjoc.19.88

Linker, loading, and reaction scale influence automated glycan assembly

• Marlene C. S. Dal Colle,
• Manuel G. Ricardo,
• Nives Hribernik,
• José Danglad-Flores,
• Peter H. Seeberger and
• Martina Delbianco

Beilstein J. Org. Chem. 2023, 19, 1015–1020, doi:10.3762/bjoc.19.77

• observed in the chromatograms of the crudes (Figure 3B). MS analysis showed the presence of capped linker (*), capped dimer (†), and Lev-containing dimer (‡) (see Figures S5 and S7 in Supporting Information File 1). No significant variations were noticed within each series of experiments, with slightly

• showed the presence of capped linker (*), capped dimer (†), and Lev-containing dimer (‡). The monosaccharides are represented following the symbol nomenclature for glycans (SNFG). Supporting Information Supporting Information File 120: Experimental procedures and characterization data. Funding We thank

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

• pursuit of HBC-tetramer-based supertwistacene (compound 115 in Scheme 12), Wang and co-workers synthesized a chiral HBC-dimer 46 [46], in which two HBC units structurally shared one benzene ring (Scheme 6). 1,4-Bis((4-(tert-butyl)phenyl)ethynyl)benzene reacted with tetracyclone 2 through a two-fold Diels

• the P,P, and M,M enantiomers. The isomerization barrier was determined as 44.7 kcal/mol at 260 °C by HPLC analysis. Meanwhile, Campaña and co-workers reported a similar chiral, tropone-containing HBC-dimer 53 [47]. Ketone 47 was transformed to compound 48 by reacting with 1-iodo-4-(phenylethynyl

• trimethylsilylacetylene and monobromo 78 afforded HBD-dimer 79. Then the Diels–Alder reaction of compound 79 and tetracyclone 80 gave compound 81 in a medium yield. Due to the crowdedness of adjacent HBC units, a chiral [7]helicene 82 was formed during the Scholl reaction of precursor 81. Campaña and co-workers

Cassane diterpenoids with α-glucosidase inhibitory activity from the fruits of Pterolobium macropterum

• Sarot Cheenpracha,
• Ratchanaporn Chokchaisiri,
• Lucksagoon Ganranoo,
• Sareeya Bureekaew,
• Thunwadee Limtharakul and
• Surat Laphookhieo

Beilstein J. Org. Chem. 2023, 19, 658–665, doi:10.3762/bjoc.19.47

• resulted in the isolation of one new cassane diterpenoid, 14β-hydroxycassa-11(12),13(15)-dien-12,16-olide (1), one new caged cassane diterpenoid dimer featuring a 6/6/6/6/6/5/6/6/6 nonacyclic ring system, 6′-acetoxypterolobirin B (3), and one known compound (Figure 1). Results and Discussion The fruits of

• diterpenoid dimer with unique 6/6/6/6/6/5/6/6/6 nonacyclic ring system. The minor difference was the additional acetoxy group (δH 2.10) at C-6′. This conclusion was suggested by the HMBC correlations (Figure 2) from H-6′ to 6′-OCOCH3 (δC 170.4) and C-10′ (δC 36.8), and from H3-20′ to C-5′ (δC 55.1) and C-10

Phenanthridine–pyrene conjugates as fluorescent probes for DNA/RNA and an inactive mutant of dipeptidyl peptidase enzyme

• Josipa Matić,
• Tana Tandarić,
• Marijana Radić Stojković,
• Filip Šupljika,
• Zrinka Karačić,
• Ana Tomašić Paić,
• Lucija Horvat,
• Robert Vianello and
• Lidija-Marija Tumir

Beilstein J. Org. Chem. 2023, 19, 550–565, doi:10.3762/bjoc.19.40

• Information File 1). Compound Phen-Py-1 showed high, micromolar/submicromolar affinities for all examined polynucleotides. The binding of Phen-Py-1 to polynucleotides possibly led to the unstacking of intramolecular pyrene–phenanthridine dimer and consequent excimer fluorescence quenching independently of the

Transition-metal-catalyzed domino reactions of strained bicyclic alkenes

• Austin Pounder,
• Eric Neufeld,
• Peter Myler and
• William Tam

Beilstein J. Org. Chem. 2023, 19, 487–540, doi:10.3762/bjoc.19.38

Transition-metal-catalyzed C–H bond activation as a sustainable strategy for the synthesis of fluorinated molecules: an overview

• Louis Monsigny,
• Floriane Doche and
• Tatiana Besset

Beilstein J. Org. Chem. 2023, 19, 448–473, doi:10.3762/bjoc.19.35

• 30% yield. A careful monitoring of the reaction unveiled the rapid formation of the CF3SeSeCF3 dimer, which could be the active trifluoromethylselenolating reagent in this transformation. In 2022, Magnier, Billard and co-workers applied the previous methodology to the trifluoromethylselenolation of

Mechanochemical solid state synthesis of copper(I)/NHC complexes with K₃PO₄

• Ina Remy-Speckmann,
• Birte M. Zimmermann,
• Mahadeb Gorai,
• Martin Lerch and
• Johannes F. Teichert

Beilstein J. Org. Chem. 2023, 19, 440–447, doi:10.3762/bjoc.19.34

• procedure: steel vessel (12 mL), 6 steel balls (1 cm diameter), 450 rpm, 4 h). (dimer = [(NHC)2Cu+]Cl−). Supporting Information Supporting Information File 36: General procedures, experimental details, analytical data and copies of NMR spectra. Acknowledgements Prof. Dr. Martin Oestreich (TU Berlin) is

Combretastatins D series and analogues: from isolation, synthetic challenges and biological activities

• Jorge de Lima Neto and
• Paulo Henrique Menezes

Beilstein J. Org. Chem. 2023, 19, 399–427, doi:10.3762/bjoc.19.31

• ether moiety. The best result was obtained when phenol 101 was subjected to anodic oxidation, leading to the formation of spiro-dimer 102 in 61% yield. Protection of the alcohol using TBSOTf followed by cyclic ether cleavage and re-aromatization gave compound 104. Subsequent dehalogenation followed by

CuAAC-inspired synthesis of 1,2,3-triazole-bridged porphyrin conjugates: an overview

• Dileep Kumar Singh

Beilstein J. Org. Chem. 2023, 19, 349–379, doi:10.3762/bjoc.19.29

• ascorbate in DMSO (Scheme 9). According to UV–vis and circular dichroism (CD) spectrum measurements, the authors state that the formation of the dimer of porphyrin 50 can be attributed to DNA hybridization and through-space electronic interactions. In this investigation, it was found that the DNA serves as

• -porphyrin and copper-corrole moieties upon photoexcitation. Moreover, the theoretical calculations suggested that the porphyrin moiety acted as a donor while the corrole unit acted as an acceptor in dimer 60. Recently S. Y. Yap and co-workers [38] used “click chemistry” to link a water-soluble porphyrin

Group 13 exchange and transborylation in catalysis

• Dominic R. Willcox and
• Stephen P. Thomas

Beilstein J. Org. Chem. 2023, 19, 325–348, doi:10.3762/bjoc.19.28

• frustrated Lewis pair (FLP)-mediated C‒H functionalisation (Scheme 4a). Using computational analysis, the mechanism of the reaction was proposed to occur by borane dimer [9]2 dissociation, followed by a concerted deprotonation of the heterocycle 10 to give a zwitterionic intermediate 11. The zwitterion then

Synthesis and reactivity of azole-based iodazinium salts

• Thomas J. Kuczmera,
• Annalena Dietz,
• Andreas Boelke and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2023, 19, 317–324, doi:10.3762/bjoc.19.27

• mixture was stirred for 14 d at 65 °C. a6.00 mmol scale, T = 50 °C, bT = 40 °C, cT = 80 °C, t = 6 d, dt = 7 d, e0.3 equiv of DCM were included in the product. Single crystal structures (ORTEP drawing with 50% probability) of the pyrazole-coordinated salt 5bb (dimer, a second structure was omitted for

An accelerated Rauhut–Currier dimerization enabled the synthesis of (±)-incarvilleatone and anticancer studies

• Tharun K. Kotammagari,
• Sweta Misra,
• Sayantan Paul,
• Sunita Kunte,
• Rajesh G. Gonnade,
• Manas K. Santra and
• Asish K. Bhattacharya

Beilstein J. Org. Chem. 2023, 19, 204–211, doi:10.3762/bjoc.19.19

• structure of rac-incarvilleatone (1) was determined by spectroscopic methods and single crystal X-ray analysis. However, they were unable to obtain single crystals of either of the enantiomers (−)-incarvilleatone [(−)-1] and (+)-incarvilleatone [(+)-1]. (±)-Incarviditone (2), a novel benzofuranone dimer was

• isolated from I. delavayi along with known (±)-rengyolone (3) [2]. (±)-Incarviditone (2) presents a new carbon-skeleton by being the first benzofuranone dimer connected by a C–C bond. The cytotoxicity of (±)-incarviditone (2) has been assayed against cell lines A549, LOVO, HL-60, 6TCEM, and HepG2 and

1,4-Dithianes: attractive C2-building blocks for the synthesis of complex molecular architectures

• Bram Ryckaert,
• Ellen Demeyere,
• Frederick Degroote,
• Hilde Janssens and
• Johan M. Winne

Beilstein J. Org. Chem. 2023, 19, 115–132, doi:10.3762/bjoc.19.12

• cyclic hemithioacetal dimer). The chemistry and synthetic applications of reagent 4 and related α-thiocarbonyl substances have been reviewed in detail elsewhere [27], and they are rarely used as building blocks for 1,4-dithiane-type targets. For the synthesis of 5,6-dihydro-1,4-dithiin (2), several

• dependence [95]. On the other hand, simple benzyl cations can undergo more controlled (3 + 2) annulations, as is illustrated by the long-known Friedel–Crafts-type acid-catalyzed cascade reaction of styrene leading to the cyclic styrene dimer 86 (Scheme 13c) [96][97]. This (3 + 2) cycloaddition reactivity of

A novel spirocyclic scaffold accessed via tandem Claisen rearrangement/intramolecular oxa-Michael addition

• Anastasia Vepreva,
• Alexander Yanovich,
• Dmitry Dar’in,
• Grigory Kantin,
• Alexander Bunev and
• Mikhail Krasavin

Beilstein J. Org. Chem. 2022, 18, 1649–1655, doi:10.3762/bjoc.18.177

• synthesized as detailed in Scheme 3. The O–H insertion reaction worked well for electron-neutral or electron-rich phenols. The presence of chlorine substituents (such as 4-Cl or 2,4-diCl) in the phenol component drastically diminished the yield and led to the formation of the earlier reported DAS dimer [16

Preparation of β-cyclodextrin-based dimers with selectively methylated rims and their use for solubilization of tetracene

• Konstantin Lebedinskiy,
• Volodymyr Lobaz and
• Jindřich Jindřich

Beilstein J. Org. Chem. 2022, 18, 1596–1606, doi:10.3762/bjoc.18.170

• better effectiveness than other tested supramolecular hosts. Keywords: cyclodextrin; dimer; methylation; solubilization; tetracene; Introduction Cyclodextrins (CDs) are cyclic oligomers of glucose that play an important role in supramolecular chemistry [1]. The structure of any CD contains a

• propargyl-containing compounds, including other CDs, to form a dimer [12]. Usually, such reactions proceed with a Cu(I) catalyst [27]; however, Cu(I) can be generated in situ by the reduction of Cu(II) [12][28] or by the dissolution of metal copper [29]. Moreover, the load of the catalyst varies from

• catalytical amounts (0.02 equiv) [27] to semi-equivalent [12]. Optimal conditions for a click reaction are a subject to discovery in every case, because temperature, microwave or ultrasonic irradiation, and type of catalyst strongly influence the reaction time and yields. In the preparation of dimer 4, the

Microelectrode arrays, electrosynthesis, and the optimization of signaling on an inert, stable surface

• Kendra Drayton-White,
• Siyue Liu,
• Yu-Chia Chang,
• Sakashi Uppal and
• Kevin D. Moeller

Beilstein J. Org. Chem. 2022, 18, 1488–1498, doi:10.3762/bjoc.18.156

• pyrene to form the exciplex dimer that fluoresces in the red region of the spectrum and does not self-quench. A fluorescence microscope was then used to take an image of the array, and the image used to quantify the fluorescence, and thereby the amount of material present, at each region of the array

Computational model predicts protein binding sites of a luminescent ligand equipped with guanidiniocarbonyl-pyrrole groups

• Neda Rafieiolhosseini,
• Matthias Killa,
• Thorben Neumann,
• Niklas Tötsch,
• Jean-Noël Grad,
• Alexander Höing,
• Thies Dirksmeyer,
• Jochen Niemeyer,
• Christian Ottmann,
• Shirley K. Knauer,
• Michael Giese,
• Jens Voskuhl and
• Daniel Hoffmann

Beilstein J. Org. Chem. 2022, 18, 1322–1331, doi:10.3762/bjoc.18.137

• -3-3ζ homodimer [14]. Very recently the survivin–histone H3 interaction was disrupted using a GCP dimer, which led to decreased cancer cell proliferation [8]. A major problem in this context is the readout of binding events, which is currently mainly achieved by indirect measurements. One approach to

• potential supramolecular ligand for 14-3-3ζ. We synthesized a GCP-Lys dimer coupled via Cu(I)-catalyzed click reaction to the chosen emitter equipped with two azide functions (Figure 1 and Supporting Information File 1) and investigated the photophysical properties in detail (Supporting Information File 1

• of the omega in the case without C-Raf; thirdly, above the pore between the two binding grooves of the omega in the presence of C-Raf. Overall, the clustering and the pattern of energies reflect the C2 symmetry of the 14-3-3ζ dimer. Minimum energy conformations Closer inspection of energies reveals

Polymer and small molecule mechanochemistry: closer than ever

• José G. Hernández

Beilstein J. Org. Chem. 2022, 18, 1225–1235, doi:10.3762/bjoc.18.128

• is observed [46]. This difference is believed to be related to the exertion of tensile forces along the glycosidic linkage of the polymer chain during ball milling, which may lower the activation energy for the depolymerization of chitin. Indeed, DFT calculations using the N-acetylglucosamine dimer

• as the model compound showed that the application of pulling forces to selected atoms in the dimer perturb the reaction, making the depolymerization easier to occur [45]. In contrast, no change in the activation energy of the deacetylation step was observed with the introduction of the pulling forces

Derivatives of benzo-1,4-thiazine-3-carboxylic acid and the corresponding amino acid conjugates

• Péter Kisszékelyi,
• Tibor Peňaška,
• Klára Stankovianska,
• Mária Mečiarová and
• Radovan Šebesta

Beilstein J. Org. Chem. 2022, 18, 1195–1202, doi:10.3762/bjoc.18.124

• different temperatures under classical conditions and even under MWI (Table 1, entries 12 and 13). Also, reactions with 6,6'-disulfanediylbis(3-methoxyaniline) were unsuccessful. Having observed dimer formation during the syntheses of benzothiazines, we have attempted to synthesize the corresponding dimer

• directly. To that end, we attempted reactions from aminothiol 8a as well as from the corresponding disulfide, both at room temperature and under MWI. In these experiments, the yield of dimer 11a was in the range of 10–34%. We also tried to enhance the oxidative dimerization using a mild oxidizing agent

• . The use of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in 1,4-dioxane afforded the dimer 11a in a slightly better yield of 46% (Scheme 2). For all the prepared benzothiazine derivatives 10 we observed some degree of instability. The derivatives were reasonably stable in the solid state but usually