Hetero-polycyclic aromatic systems: A data-driven investigation of structure–property relationships

• Sabyasachi Chakraborty,
• Eduardo Mayo Yanes and
• Renana Gershoni-Poranne

Beilstein J. Org. Chem. 2024, 20, 1817–1830, doi:10.3762/bjoc.20.160

• distributions of five molecular properties: highest occupied molecular orbital (HOMO) energy, lowest unoccupied molecular orbital (LUMO) energy, HOMO–LUMO gap (Gap), adiabatic ionization potential (AIP), and adiabatic electron affinity (AEA). As shown in the violin plots in Figure 3B, for all properties, the

Divergent role of PIDA and PIFA in the AlX₃ (X = Cl, Br) halogenation of 2-naphthol: a mechanistic study

• Kevin A. Juárez-Ornelas,
• Manuel Solís-Hernández,
• Pedro Navarro-Santos,
• J. Oscar C. Jiménez-Halla and
• César R. Solorio-Alvarado

Beilstein J. Org. Chem. 2024, 20, 1580–1589, doi:10.3762/bjoc.20.141

• reference. At this stage, the PIDA–AlBr3 adduct undergoes ionization, giving rise to the corresponding ion pair I-1–Br (ΔG = −31.3 kcal/mol) in a highly exergonic and energetically favorable process. Next, an intramolecular SN2 reaction of the formed aluminum anion transfers a bromine atom to the

Towards an asymmetric β-selective addition of azlactones to allenoates

• Behzad Nasiri,
• Ghaffar Pasdar,
• Paul Zebrowski,
• Katharina Röser,
• David Naderer and
• Mario Waser

Beilstein J. Org. Chem. 2024, 20, 1504–1509, doi:10.3762/bjoc.20.134

• Thermo Fisher Scientific LTQ Orbitrap XL spectrometer with an Ion Max API source and analyses were made in the positive ionization mode if not otherwise stated. Infrared (IR) spectra were recorded on a Bruker Alpha II FTIR spectrometer with diamond ATR-module using the OPUS software package and are

Diameter-selective extraction of single-walled carbon nanotubes by interlocking with Cu-tethered square nanobrackets

• Guoqing Cheng and
• Naoki Komatsu

Beilstein J. Org. Chem. 2024, 20, 1298–1307, doi:10.3762/bjoc.20.113

• diameter 0.8– 1.2 nm) were used. For centrifugal operation, Avanti J-E of Beckman Coulter and Hitachi Himac CS 150 GC II were used. Mass spectra were recorded on Bruker Autoflex III using the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) method with anthracene as the matrix for all

Mechanistic investigations of polyaza[7]helicene in photoredox and energy transfer catalysis

• Johannes Rocker,
• Till J. B. Zähringer,
• Matthias Schmitz,
• Till Opatz and
• Christoph Kerzig

Beilstein J. Org. Chem. 2024, 20, 1236–1245, doi:10.3762/bjoc.20.106

• as the ionization product resulting from a consecutive two-photon absorption at the selected high laser intensity [69][70], yielding the corresponding long-lived radical cation with second-order decay that is typical for oxidized/reduced species, and a solvated electron as by-product. The latter is

• as the radical cation, Aza-H•+, which is in perfect agreement with our proposed photoinduced electron transfer step, while no triplet-excited Aza-H is observed (Figure 2A, blue spectrum). Since the direct ionization of Aza-H also contributes to this spectrum, we recorded a spectrum of only Aza-H in

• competes with ionization already during the laser pulse. Kinetic measurements of the radical cation species show multiexponential decay, probably due to recombination of the radical cation and radical anion (Figure 2A, inset). Despite the reported absorption maximum for 4CP•− at 398 nm [72], we were unable

Two-fold addition reaction of silylene to C₆₀: structural and electronic properties of a bis-adduct

• Masahiro Kako,
• Masato Kai,
• Masanori Yasui,
• Michio Yamada,
• Yutaka Maeda and
• Takeshi Akasaka

Beilstein J. Org. Chem. 2024, 20, 1179–1188, doi:10.3762/bjoc.20.100

• perpendicularly. Unfortunately, the matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry of 3 afforded no molecular ion peak expected for adducts derived from Dip2Si and C60 while a base peak at m/z 720 due to C60 was observed probably because of the low stability of radical

Kinetically stabilized 1,3-diarylisobenzofurans and the possibility of preparing large, persistent isoacenofurans with unusually small HOMO–LUMO gaps

• Qian Liu and
• Glen P. Miller

Beilstein J. Org. Chem. 2024, 20, 1099–1110, doi:10.3762/bjoc.20.97

• Center using a peak-matching protocol to determine the mass and error range of the molecular ion, and employing electrospray as the ionization technique. UV–vis absorption spectra were measured with a Varian Cary 50 Scan UV–visible spectrophotometer and corrected for background signal with a solvent

Spin and charge interactions between nanographene host and ferrocene

• Akira Suzuki,
• Yuya Miyake,
• Ryoga Shibata and
• Kazuyuki Takai

Beilstein J. Org. Chem. 2024, 20, 1011–1019, doi:10.3762/bjoc.20.89

• increment of screening effect on photoemission hole by increasing in conduction electrons. Increasing in conduction π electron of nanographene in FeCp2-ACFs-150 suggests the charge transfer from FeCp2 to ACFs. In this connection, the observed partial ionization of FeCp2 is well understood by the structure

Synthesis and properties of 6-alkynyl-5-aryluracils

• Ruben Manuel Figueira de Abreu,
• Till Brockmann,
• Alexander Villinger,
• Peter Ehlers and
• Peter Langer

Beilstein J. Org. Chem. 2024, 20, 898–911, doi:10.3762/bjoc.20.80

• ). Samples were ionized by electron impact ionization (EI) on an Agilent 6890/5973 or Agilent 7890/5977 GC–MS equipped with a HP-5 capillary column using helium carrier gas or by electron spray ionization (ESI) on an Agilent 1200/6210 time-of-flight (TOF) LC–MS. X-ray single-crystal structure analysis was

Activity assays of NnlA homologs suggest the natural product N-nitroglycine is degraded by diverse bacteria

• Kara A. Strickland,
• Brenda Martinez Rodriguez,
• Ashley A. Holland,
• Shelby Wagner,
• Michelle Luna-Alva,
• David E. Graham and
• Jonathan D. Caranto

Beilstein J. Org. Chem. 2024, 20, 830–840, doi:10.3762/bjoc.20.75

• , 4.6 × 150 mm) and connected to an Agilent 6230 TOF mass spectrometer with electrospray ionization (ESI). Analyses used an isocratic mixture containing 65% water, 25% acetonitrile, and 10% isopropanol at a flow rate of 0.5 mL/min. The mass spectrometer was run in the negative ion mode with a probe

Enhanced reactivity of Li⁺@C₆₀ toward thermal [2 + 2] cycloaddition by encapsulated Li⁺ Lewis acid

• Hiroshi Ueno,
• Yu Yamazaki,
• Hiroshi Okada,
• Fuminori Misaizu,
• Ken Kokubo and
• Hidehiro Sakurai

Beilstein J. Org. Chem. 2024, 20, 653–660, doi:10.3762/bjoc.20.58

• mode high-resolution matrix-assisted laser desorption ionization mass spectra showed the formation of the monoadducts at m/z 875.10431 (5a) and 861.08866 (5b), which were assigned to each molecular ion ([M]+ calcd for C70H12OLi (5a): 875.10427 and C69H10OLi (5b): 861.08862, respectively). The UV–vis

• , external standard), and carbon of the solvent for 13C (53.84 ppm, CD2Cl2). High-resolution matrix-assisted laser desorption ionization (HR-MALDI) mass spectra were obtained on a Bruker solariX 12T mass spectrometer with dithranol as a matrix. UV–vis absorption spectra were measured on a JASCO V-670 and a

Synthesis of photo- and ionochromic N-acylated 2-(aminomethylene)benzo[b]thiophene-3(2Н)-ones with a terminal phenanthroline group

• Vladimir P. Rybalkin,
• Sofiya Yu. Zmeeva,
• Lidiya L. Popova,
• Irina V. Dubonosova,
• Olga Yu. Karlutova,
• Oleg P. Demidov,
• Alexander D. Dubonosov and
• Vladimir A. Bren

Beilstein J. Org. Chem. 2024, 20, 552–560, doi:10.3762/bjoc.20.47

• ™ Impact instrument (electrospray ionization). Melting points were determined on a Fisher–Johns melting point apparatus. X-ray diffraction study The X-ray diffraction dataset of compound 3b was recorded on an Agilent SuperNova diffractometer using a microfocus X-ray radiation source with copper anode and

A new analog of dihydroxybenzoic acid from Saccharopolyspora sp. KR21-0001

• Rattiya Janthanom,
• Yuta Kikuchi,
• Hiroki Kanto,
• Tomoyasu Hirose,
• Arisu Tahara,
• Takahiro Ishii,
• Arinthip Thamchaipenet and
• Yuki Inahashi

Beilstein J. Org. Chem. 2024, 20, 497–503, doi:10.3762/bjoc.20.44

• was concentrated in vacuo to yield 1 (7.9 mg). LC–MS analysis Electrospray ionization-mass spectrometry (ESIMS) data was collected using a Triple TOF 5600+ LC–MS/MS System (AB Sciex, Framingham, MA, USA) with an ODS column (Capcell Core C18, 3.0 i.d. × 100 mm, 40 °C) (Osaka Soda, Japan) at a flow rate

Facile approach to N,O,S-heteropentacycles via condensation of sterically crowded 3H-phenoxazin-3-one with ortho-substituted anilines

• Eugeny Ivakhnenko,
• Vasily Malay,
• Pavel Knyazev,
• Nikita Merezhko,
• Nadezhda Makarova,
• Oleg Demidov,
• Gennady Borodkin,
• Andrey Starikov and
• Vladimir Minkin

Beilstein J. Org. Chem. 2024, 20, 336–345, doi:10.3762/bjoc.20.34

• Maxis™ Impact (resolving power (FWHM) of 40,000 at m/z 1222, electrospray ionization). The cyclic voltammograms of 4a–h, 5a–c, 6a,b, and 10c were measured with the use of three-electrode configuration (glassy carbon working electrode, Pt counter electrode, Ag/Ag+ reference electrode using 0.01 M AgNO3

Discovery of unguisin J, a new cyclic peptide from Aspergillus heteromorphus CBS 117.55, and phylogeny-based bioinformatic analysis of UngA NRPS domains

• Sharmila Neupane,
• Marcelo Rodrigues de Amorim and
• Elizabeth Skellam

Beilstein J. Org. Chem. 2024, 20, 321–330, doi:10.3762/bjoc.20.32

• for MS2 scan survey. Precursor ion was impacted with three different collision energies (33, 45, 57 V), and the resulting MS2 spectra were combined into one final MS2 spectrum. The mass spectra were acquired using Turbo Spray Ionization set to 5.5 kV in positive ion mode with an accumulation time of

Substitution reactions in the acenaphthene analog of quino[7,8-h]quinoline and an unusual synthesis of the corresponding acenaphthylenes by tele-elimination

• Ekaterina V. Kolupaeva,
• Narek A. Dzhangiryan,
• Alexander F. Pozharskii,
• Oleg P. Demidov and
• Valery A. Ozeryanskii

Beilstein J. Org. Chem. 2024, 20, 243–253, doi:10.3762/bjoc.20.24

• be associated with the increased basicity of the starting substrate and its structural organization (proximity of the two nitrogen atoms). The revealed inertness may also be rationalized via the ionization of the starting dipyridoacenaphthene system 5 to an anion or even dianion 7 (at least in

Photochromic derivatives of indigo: historical overview of development, challenges and applications

• Gökhan Kaplan,
• Zeynel Seferoğlu and
• Daria V. Berdnikova

Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23

• lifetimes, radiative and non-radiative relaxation pathways of the indigo chromophore [26][27][30][31][32][33][34][35] as well as to estimate ionization potentials and electronic structures [28][29], singlet oxygen generation capacity [31], QSAR properties [25], and others. In both solution and solid state

Comparison of glycosyl donors: a supramer approach

• Anna V. Orlova,
• Nelly N. Malysheva,
• Maria V. Panova,
• Nikita M. Podvalnyy,
• Michael G. Medvedev and
• Leonid O. Kononov

Beilstein J. Org. Chem. 2024, 20, 181–192, doi:10.3762/bjoc.20.18

• CFCl3 (δF 0.0). Assignments of the signals in the NMR spectra were performed using 2D-spectroscopy (COSY, HSQC, HMBC) and DEPT-135 experiments. For the copies of NMR spectra for all new compounds see Supporting Information File 1. High resolution mass spectra (electrospray ionization, HRESIMS) were

Electron-beam-promoted fullerene dimerization in nanotubes: insights from DFT computations

• Laura Abella,
• Gerard Novell-Leruth,
• Josep M. Ricart,
• Josep M. Poblet and
• Antonio Rodríguez-Fortea

Beilstein J. Org. Chem. 2024, 20, 92–100, doi:10.3762/bjoc.20.10

• + C60 to assess the effect ionization produced by the electron beam has in the process. Before the reaction takes place, a stabilizing van der Waals complex between the two C60 molecules was formed (Figure 2), with an interdimer distance around 3 Å (slightly larger for the neutral profile). For dimer 1

Identification of the p-coumaric acid biosynthetic gene cluster in Kutzneria albida: insights into the diazotization-dependent deamination pathway

• Seiji Kawai,
• Akito Yamada,
• Yohei Katsuyama and
• Yasuo Ohnishi

Beilstein J. Org. Chem. 2024, 20, 1–11, doi:10.3762/bjoc.20.1

• and evaporated completely in vacuo. The residual materials were dissolved in 200 µL of methanol. The obtained samples were analyzed by liquid chromatography–electrospray ionization mass spectrometry (LC–ESIMS) using an LC-2040C 3D Plus system (Shimazu Corp., Kyoto, Japan) equipped with a COSMOCORE

Aromatic systems with two and three pyridine-2,6-dicarbazolyl-3,5-dicarbonitrile fragments as electron-transporting organic semiconductors exhibiting long-lived emissions

• Karolis Leitonas,
• Brigita Vigante,
• Dmytro Volyniuk,
• Audrius Bucinskas,
• Pavels Dimitrijevs,
• Sindija Lapcinska,
• Pavel Arsenyan and
• Juozas Vidas Grazulevicius

Beilstein J. Org. Chem. 2023, 19, 1867–1880, doi:10.3762/bjoc.19.139

• of the compounds are sensitive to the medium. Cyclic voltammetry measurements indicate good hole-blocking and electron-injecting properties due to their high ionization potentials. Photoelectron spectroscopy and time-of-flight measurements reveal good electron-transporting properties for one of the

• results of CV measurements were used to obtain the ionization potential (IPCV) and electron affinity (EACV) values of the compounds 6–9. These values were obtained using the following equations: IPCV = e (Eonset,red − Fconset + 4.8), EACV = e (Eonset,ox − Fconset + 4.8) [7]. The IPCV values fall in a

• range of 5.80–5.90 eV, while the electron affinities (EACV) vary from 3.20 to 3.33 eV (Table 1). The obtained values are comparable to the corresponding ionization potentials (IPPE) and electron affinities (EAPE) obtained for the films by photoelectron emission spectrometry, presented and discussed in

Controlling the reactivity of La@C₈₂ by reduction: reaction of the La@C₈₂ anion with alkyl halide with high regioselectivity

• Yutaka Maeda,
• Saeka Akita,
• Mitsuaki Suzuki,
• Michio Yamada,
• Takeshi Akasaka,
• Kaoru Kobayashi and
• Shigeru Nagase

Beilstein J. Org. Chem. 2023, 19, 1858–1866, doi:10.3762/bjoc.19.138

• , such as alkyl halides. In this study, the thermal reaction of the La@C2v-C82 anion with benzyl bromide derivatives 1 at 110 °C afforded single-bonded adducts 2–5 with high regioselectivity. The products were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

• -electron reduction of Gd@C2v-C82 for the addition reaction to occur at room temperature [22]. Supporting Information File 1, Figure S1 depicts the three HPLC separation steps including recycling for the isolation. The matrix-assisted laser desorption/ionization time-of-flight (MALDI–TOF) mass spectra of 2a

• reduction of La@C2v-C82 is an easy and effective method for controlling its reactivity and selectivity via ionization for the production of La@C2v-C82 derivatives. Experimental General: All chemicals and solvents were obtained from Wako, TCI, and Aldrich and were used without further purification unless

Thienothiophene-based organic light-emitting diode: synthesis, photophysical properties and application

• Recep Isci and
• Turan Ozturk

Beilstein J. Org. Chem. 2023, 19, 1849–1857, doi:10.3762/bjoc.19.137

• (OFETs) [26][27][28], capacitors [29][30], hybrid films [31], and photosensitizers [32][33][34]. Another important π-conjugated unit is triphenylamine (TPA), having an ionization potential of 6.80 eV, which is lower compared to many other organic cores, thus providing a strong electron-donating ability

Substituent-controlled construction of A₄B₂-hexaphyrins and A₃B-porphyrins: a mechanistic evaluation

• Seda Cinar,
• Dilek Isik Tasgin and
• Canan Unaleroglu

Beilstein J. Org. Chem. 2023, 19, 1832–1840, doi:10.3762/bjoc.19.135

• reaction mechanism of the presented method was studied on model reactions by electrospray-ionization time-of-flight (HRESI–TOF) mass spectral analysis in a timely manner. The analytical results indicated that the observed azafulvene-ended di- and tripyrrolic intermediates are responsible for the formation

• product formation, mass spectral analyses of model reactions were investigated by time-dependent electrospray-ionization time-of-flight (HRESI–TOF) technique. Results and Discussion Reactions of meso-pentafluorophenyl-substituted A2-tripyrrane 1 and N-tosylimines 2 were performed in the presence of Cu(OTf

• certain time intervals within 2 hours and examined by ESI LC–MS. Throughout the high-resolution electrospray-ionization time-of-flight (HRESI–TOF) mass analysis of the reaction mixture at 0 °C, the following peaks were observed: m/z = 246.0366 ([M + H]+ calcd for C11H5F5N, 246.0337), m/z = 857.1468 ([M

A novel recyclable organocatalyst for the gram-scale enantioselective synthesis of (S)-baclofen

• Gyula Dargó,
• Dóra Erdélyi,
• Balázs Molnár,
• Péter Kisszékelyi,
• Zsófia Garádi and
• József Kupai

Beilstein J. Org. Chem. 2023, 19, 1811–1824, doi:10.3762/bjoc.19.133

• ionization. HPLC–MS was performed on an HPLC system using a Shimadzu LCMS-2020 (Shimadzu Corp., Japan) device equipped with a Reprospher (Altmann Analytik Corp., Germany) 100 Å C18 (5 µm; 100 × 3 mm) column and a positive/negative double ion source with a quadrupole MS analyzer in the range of 50–1000 m/z