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

Selectivity control towards CO versus H₂ for photo-driven CO₂ reduction with a novel Co(II) catalyst

• Lisa-Lou Gracia,
• Philip Henkel,
• Olaf Fuhr and
• Claudia Bizzarri

Beilstein J. Org. Chem. 2023, 19, 1766–1775, doi:10.3762/bjoc.19.129

• otherwise specified. Gaseous products were determined by a gas chromatograph equipped with two barrier discharge ionization detectors (GC–BID). Typically, the concentrations used for the first screening were: 1 mM for PS, 0.1 mM for catalyst 1, and 20 mM for BIH, and the bases used were either

• from Shimadzu (GC-2030) equipped with two barrier discharge ionization detectors (BID). Every test was repeated at least twice. The photon flux was evaluated with actinometry, according to a previously published procedure [42], and it was 0.025 µE s−1. Therefore, an apparent photoluminescent quantum

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

• wide range of semiconductors, they must exhibit low ionization energies and thus air sensitivity. One approach to circumvent this issue is to identify systems where the electron-transfer process is coupled to other chemical reactions, increasing the kinetic stability of the dopant to air, and thus

• their Y = cyclohexyl counterparts, 1e+/1e• and 1h+/1h•, respectively. These differences are also similar to those previously seen in the comparison of Y = metallocenyl systems 1c+/1c• and 1d+/1d• with 1e+/1e• (and in the DFT-calculated ionization energies of 1c–e•) [14][50] and are perhaps surprising

Sulfur-containing spiroketals from Breynia disticha and evaluations of their anti-inflammatory effect

• Ken-ichi Nakashima,
• Naohito Abe,
• Masayoshi Oyama,
• Hiroko Murata and
• Makoto Inoue

Beilstein J. Org. Chem. 2023, 19, 1604–1614, doi:10.3762/bjoc.19.117

• electrospray ionization HRESIMS analysis, and quantum chemical electronic CD calculations. Furthermore, the absolute configurations of sugar residues were determined by derivatization of the hydrolysates with ʟ-cysteine methyl ester and o-tolyl isothiocyanate followed by HPLC analysis. The anti-inflammatory

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

• , emitted from the surface of polymers [178]. When a high-energy photon impacts an atomic electron, part of the photon energy is transferred to the electron leading to excitation or ionization and radical formation, and a deflected photon with lower energy is emitted, ready to impact another electron. This

Two new lanostanoid glycosides isolated from a Kenyan polypore Fomitopsis carnea

• Winnie Chemutai Sum,
• Sherif S. Ebada,
• Didsanutda Gonkhom,
• Cony Decock,
• Rémy Bertrand Teponno,
• Josphat Clement Matasyoh and
• Marc Stadler

Beilstein J. Org. Chem. 2023, 19, 1161–1169, doi:10.3762/bjoc.19.84

• speed ETD ion trap mass spectrometer (Bruker Daltonics, Bremen, Germany) for HPLC-DAD/MS in positive and negative ionization modes. The HPLC (Dionex UltiMate 3000 UHPLC, Thermo Fisher Scientific Inc., Waltham, MA, USA) system’s stationary phase was composed of a C18 Acquity UPLC BEH column (Waters

• at 0.6 mL/min and the UV–vis detection made at 210 nm and 190–600 nm. The isolates were analyzed on a MaXis ESI-TOF (time-of-flight) mass spectrometer (Bruker Daltonics) for the HRESIMS data, in the positive ionization mode. This was coupled to an Agilent 1260 series HPLC–UV system (Agilent

Synthesis of aliphatic nitriles from cyclobutanone oxime mediated by sulfuryl fluoride (SO₂F₂)

• Xian-Lin Chen and
• Hua-Li Qin

Beilstein J. Org. Chem. 2023, 19, 901–908, doi:10.3762/bjoc.19.68

• nitriles 3ba–da in excellent yields. Interestingly, when the loading of CH3COOK was reduced to 2 equivalents, we obtained a mixture of unsaturated nitrile 3aa and saturated nitrile 4 after column chromatography (Scheme 4). We speculated that the reduction of the base equivalent may induce the ionization of

Recommendations for performing measurements of apparent equilibrium constants of enzyme-catalyzed reactions and for reporting the results of these measurements

• Robert N. Goldberg,
• Robert T. Giessmann,
• Peter J. Halling,
• Carsten Kettner and
• Hans V. Westerhoff

Beilstein J. Org. Chem. 2023, 19, 303–316, doi:10.3762/bjoc.19.26

• has occurred at a microscopic level and from both directions of reaction. Binding, ionization, and reactions that involve the formation of complexes often proceed rapidly. In such cases, the assumption is generally made that equilibrium has been achieved. In any case, any assumption regarding the

Investigation of cationic ring-opening polymerization of 2-oxazolines in the “green” solvent dihydrolevoglucosenone

• Solomiia Borova and
• Robert Luxenhofer

Beilstein J. Org. Chem. 2023, 19, 217–230, doi:10.3762/bjoc.19.21

• . Size exclusion chromatography and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry were performed to determine the molar mass of the resulting polymers. Our work shows clearly that the solvent is not inert under the conditions typically used for the cationic ring-opening

• polymerization process. Further work will be necessary to establish whether a living polymerization can be achieved by additional adjustments. Keywords: 2-alkyl-2-oxazolines; matrix-assisted laser desorption/ionization mass spectrometry; nuclear magnetic resonance; polymerization kinetics; Introduction

• ). Obtained data were processed with Win-GPC software. Matrix-assisted laser desorption/ionization time-of-flight mass spectra (MALDI-TOF MS) were recorded on an Autoflex II (Bruker Daltonics, Bremen, Germany) using an N2 laser (λ = 337 nm). All spectra were recorded in positive reflector mode. Detection was

Improving the accuracy of ³¹P NMR chemical shift calculations by use of scaling methods

• William H. Hersh and
• Tsz-Yeung Chan

Beilstein J. Org. Chem. 2023, 19, 36–56, doi:10.3762/bjoc.19.4

• complicated by water solvation, as well as ionization or aggregation of the phosphoric acid in water, and calculation as a gas-phase chemical shift is also unreasonable [51]. Because of these issues, other studies have used PH3 as an alternative theoretical reference standard [18][19], despite the fact that

Digyalipopeptide A, an antiparasitic cyclic peptide from the Ghanaian Bacillus sp. strain DE2B

• Adwoa P. Nartey,
• Aboagye K. Dofuor,
• Kofi B. A. Owusu,
• Anil S. Camas,
• Hai Deng,
• Marcel Jaspars and
• Kwaku Kyeremeh

Beilstein J. Org. Chem. 2022, 18, 1763–1771, doi:10.3762/bjoc.18.185

• to be C51H89N7O13 based on the high resolution electrospray ionization mass spectrometry (HRESIMSMS) at m/z 1008.6610 for [M + H]+ similar to the calculated value of m/z 1008.6591 with Δ = −1.9 ppm. The molecular formula indicated 11 degrees of unsaturation and the analyses of the 13C NMR spectrum

• and NOESY correlations for compound 1. Liquid chromatography high resolution electrospray ionization mass spectrometry (LC–HRESIMS) sequence tags for compound 1. The absolute stereochemistry of compound 1. Global natural products social molecular networking (GNPS). 1H NMR and 13C NMR spectroscopic

Synthesis of the biologically important dideuterium-labelled adenosine triphosphate analogue ApppI(d₂)

• Petri A. Turhanen

Beilstein J. Org. Chem. 2022, 18, 1466–1470, doi:10.3762/bjoc.18.153

• for the purification of ApppI(d2) [21]. HRMS spectra were recorded on a qTOF mass spectrometer using electrospray ionization (ESI) in negative mode. The purity of the products was determined from the 1H and 31P NMR spectra to be ≥95%, unless stated otherwise. ApppI(d2)⋅3.25 and ⋅5.25 TBA salts: ATP

Characterization of a new fusicoccane-type diterpene synthase and an associated P450 enzyme

• Jia-Hua Huang,
• Jian-Ming Lv,
• Liang-Yan Xiao,
• Qian Xu,
• Fu-Long Lin,
• Gao-Qian Wang,
• Guo-Dong Chen,
• Sheng-Ying Qin,
• Dan Hu and
• Hao Gao

Beilstein J. Org. Chem. 2022, 18, 1396–1402, doi:10.3762/bjoc.18.144

• ionization mass spectrometry (HRESIMS), the molecular formula of 1 was deduced as C20H32, indicating that 1 has five degrees of unsaturation. The 13C NMR spectrum showed that there are four olefinic carbons (δC 153.2, 137.4, 125.1, 118.6) in 1. We thus reasoned that 1 features a tricyclic system

Preparation of an advanced intermediate for the synthesis of leustroducsins and phoslactomycins by heterocycloaddition

• Anaïs Rousseau,
• Guillaume Vincent and
• Cyrille Kouklovsky

Beilstein J. Org. Chem. 2022, 18, 1385–1395, doi:10.3762/bjoc.18.143

• solvent using residual chloroform (7.26 ppm) as an internal reference. 13C NMR spectra were measured at 62.5, 75 or 90 MHz using residual chloroform (77.1 ppm) as an internal reference. High-resolution mass spectrometry (HRMS) analyses were conducted with electro spray ionization (ESI). 6

Cyclodextrin-based Schiff base pro-fragrances: Synthesis and release studies

• Attila Palágyi,
• Jindřich Jindřich,
• Juraj Dian and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2022, 18, 1346–1354, doi:10.3762/bjoc.18.140

• equipped with a flame-ionization detector using a DB624 column). The GC settings were set as follows: detector temperature, 250 °C; column temperature: 160 °C for benzaldehyde and 5-methylfurfural and 120 °C for heptanal. The retention times under the given conditions were 2.1 min for benzaldehyde (2d) and

Experimental and theoretical studies on the synthesis of 1,4,5-trisubstituted pyrrolidine-2,3-diones

• Nguyen Tran Nguyen,
• Vo Viet Dai,
• Nguyen Ngoc Tri,
• Luc Van Meervelt,
• Nguyen Tien Trung and
• Wim Dehaen

Beilstein J. Org. Chem. 2022, 18, 1140–1153, doi:10.3762/bjoc.18.118

• spectrometer (Synapt G2 HDMS, Waters, Milford, MA). Samples were infused at 3 μL/min and spectra were obtained in positive (or negative) ionization mode with a resolution of 15000 (FWHM) using leucine enkephalin as lock mass. Besides, exact mass measurements were also recorded on a SCIEX X500 QTOF with

• electrospray ionization (ESI) source in a positive mode. The temperatures of the source were set at 300 °C. Curtain gas (25 psi) chambers were filled with high-purity nitrogen. The capillary voltage was constantly kept at 5500 V. Collision energies was set at 10 V and zero collision energy spread. IDA mode was

Synthesis of N-phenyl- and N-thiazolyl-1H-indazoles by copper-catalyzed intramolecular N-arylation of ortho-chlorinated arylhydrazones

• Yara Cristina Marchioro Barbosa,
• Guilherme Caneppele Paveglio,
• Claudio Martin Pereira de Pereira,
• Sidnei Moura,
• Cristiane Storck Schwalm,
• Gleison Antonio Casagrande and
• Lucas Pizzuti

Beilstein J. Org. Chem. 2022, 18, 1079–1087, doi:10.3762/bjoc.18.110

• electrospray ionization (ESI) source (MicrOTOF-QII, Bruker Scientific) in positive mode. The compounds were individually dissolved in a solution of 50% chromatographic grade MeCN and 50% deionized H2O + 0.1% formic acid. General experimental procedure for the synthesis of hydrazones 1a–i In a 100 mL round

On Reuben G. Jones synthesis of 2-hydroxypyrazines

• Pierre Legrand and
• Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 935–943, doi:10.3762/bjoc.18.93

• description of the experimental set up is provided in Supporting Information File 1. The low-resolution mass spectra were obtained on an Agilent 1200 series LC/MSD system using an Agilent Jet-Stream atmospheric electrospray ionization system and the high-resolution mass spectra (HRMS) were obtained using a

Synthesis of a new water-soluble hexacarboxylated tribenzotriquinacene derivative and its competitive host–guest interaction for drug delivery

• Man-Ping Li,
• Nan Yang and
• Wen-Rong Xu

Beilstein J. Org. Chem. 2022, 18, 539–548, doi:10.3762/bjoc.18.56

• recorded using either the ultrafleXtreme MALDI-TOF mass spectrometer (Bruker) with α-cyano-4-hydroxycinnamic acid (HCCA) as a matrix, or by electrospray ionization (ESI) on a Waters G2-XS QTOF instrument connected to a Waters H-class UPLC equipped with a Waters BEH C18 column using an eluent consisting of

Synthesis of 3,4,5-trisubstituted isoxazoles in water via a [3 + 2]-cycloaddition of nitrile oxides and 1,3-diketones, β-ketoesters, or β-ketoamides

• Md Imran Hossain,
• Md Imdadul H. Khan,
• Seong Jong Kim and
• Hoang V. Le

Beilstein J. Org. Chem. 2022, 18, 446–458, doi:10.3762/bjoc.18.47

• using an OptiMelt automated melting point system. Exact high-resolution mass determinations were analyzed on a JEOL AccuToF 4G LCplus atmospheric pressure ionization time-of-flight mass spectrometer (Jeol, Tokyo, Japan) fitted with direct analysis in real-time (DART) ion source (IonSense DART controller

Cs₂CO₃-Promoted reaction of tertiary bromopropargylic alcohols and phenols in DMF: a novel approach to α-phenoxyketones

• Ol'ga G. Volostnykh,
• Olesya A. Shemyakina,
• Anton V. Stepanov and
• Igor' A. Ushakov

Beilstein J. Org. Chem. 2022, 18, 420–428, doi:10.3762/bjoc.18.44

• , thickness of stationary phase film 0.25 μm; injector temperature 250 °C, gas carrier – helium, flow rate 0.7 mL/min; detector temperature 250 °C; mass analyzer: quadrupole, electron ionization, electron energy: 70 eV, ion source temperature 200 °C; mass range 34–650 Da. The solvent was distilled DMF. Column