Quinoxaline derivatives as attractive electron-transporting materials

• Zeeshan Abid,
• Liaqat Ali,
• Sughra Gulzar,
• Faiza Wahad,
• Raja Shahid Ashraf and
• Christian B. Nielsen

Beilstein J. Org. Chem. 2023, 19, 1694–1712, doi:10.3762/bjoc.19.124

• (Voc), underscored the influence of the molecular structure [23]. A recent development by Liang et al. introduced Qx-derived double-cable conjugated polymers as a promising approach for improving the performance of single-component-OSCs (SCOSCs). They replaced the traditional benzothiadiazole core of Y

• moieties, the resulting PCE falls slightly short. This observation highlights the importance of a careful choice of auxiliary acceptors to ensure optimal device performance [42]. Godfroy and colleagues also emphasized the significance of molecular structure and backbone planarity in achieving efficient

• charge transport in DSSCs. Their work highlights the importance of molecular structure and backbone planarity in achieving efficient charge transport in DSSCs. The sensitizers, Qx36 and Qx37, employing Qx and dithieno[3,2-f:2',3'-h]quinoxaline acceptors, respectively, showed narrower absorption spectra

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

• nitrogen in the middle of the ether chain of 19-Cr. The reaction between in situ generated 17-K2 or 19-K2 and CoCl2 produced paramagnetic cobalt(II) complexes 17-Co or 19-Co [67]. The XRD analysis of 17-Co revealed a molecular structure with distorted octahedral Co(II) coordinating water and hydroxide

• ligands. Compound 19-Co (structure not shown) retained the cobalt(II) oxidation state with a water molecule within the cleft. The XRD analysis of the structures of 19-Co and 18b-Co exhibited Pacman conformation. The X-ray molecular structure of 19-Co provided further insights, showing a square-planar

• ) complex 40-Cu formation proving that 40 acts as a colourimetric sensor. The reaction of 38 with pyrrole in the presence of BF3:Et2O resulted in 41 incorporating a single pyrrole ring [132]. The attempted oxidation with DDQ afforded fused macrocycle 42 (Scheme 11). The X-ray molecular structure of 42

Cyclodextrins permeabilize DPPC liposome membranes: a focus on cholesterol content, cyclodextrin type, and concentration

• Ghenwa Nasr,
• Hélène Greige-Gerges,
• Sophie Fourmentin,
• Abdelhamid Elaissari and
• Nathalie Khreich

Beilstein J. Org. Chem. 2023, 19, 1570–1579, doi:10.3762/bjoc.19.115

• content membrane increase. Keywords: cholesterol; cyclodextrins; liposome; membrane permeability; Introduction Cyclodextrins (CDs) are a family of cyclic oligosaccharides made of glucopyranose units connected by α-1,4-glycosidic bonds. They possess a cone-shaped molecular structure with a hydrophobic

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

• ) where the molecular structure is altered. However, the incorporation of a saccharide unit or an inositol moiety is included in subsequent sections. Modulation sn-1: In 1986, Morris-Natschke et al. [129][130] reported a racemic synthesis of thioether analogues of edelfosine using thioglycerol as

Organic thermally activated delayed fluorescence material with strained benzoguanidine donor

• Alexander C. Brannan,
• Elvie F. P. Beaumont,
• Nguyen Le Phuoc,
• George F. S. Whitehead,
• Mikko Linnolahti and
• Alexander S. Romanov

Beilstein J. Org. Chem. 2023, 19, 1289–1298, doi:10.3762/bjoc.19.95

• containing a rigid benzoguanidine ligand in its molecular structure. Results and Discussion Synthesis and structure 4BGIPN was prepared in 70% yield by aromatic nucleophilic substitution reaction from 2,4,5,6-tetrafluoroisophthalonitrile and 5H-benzo[d]benzo[4,5]imidazo[1,2-a]imidazole (benzoguanidine) after

The effect of dark states on the intersystem crossing and thermally activated delayed fluorescence of naphthalimide-phenothiazine dyads

• Liyuan Cao,
• Xi Liu,
• Xue Zhang,
• Jianzhang Zhao,
• Fabiao Yu and
• Yan Wan

Beilstein J. Org. Chem. 2023, 19, 1028–1046, doi:10.3762/bjoc.19.79

• intersystem crossing (rISC) is slow, without coupling with an approximate 3LE state. These studies are useful for an in-depth understanding of the photophysical mechanisms of the TADF emitters, as well as for molecular structure design of new electron donor–acceptor TADF emitters. Keywords: charge-transfer

• harvesting efficiency of both the singlet and triplet excitons and thus a high quantum efficiency for the electroluminescence [13]. The TADF emission process involves the reverse intersystem crossing (rISC) from the triplet (T1) state to the emissive singlet (S1) state. A typical molecular structure motif

• not changed by the unique molecular structure modification method [51]. This approach is useful for studying molecules showing complicated, entangled photophysical processes upon photoexcitation, for instance the electron donor–acceptor type of TADF emitters [44][46]. Recently, we reported NI-PTZ

Cyclodextrins as building blocks for new materials

• Miriana Kfoury and
• Sophie Fourmentin

Beilstein J. Org. Chem. 2023, 19, 889–891, doi:10.3762/bjoc.19.66

• . CDs are the most studied supramolecular hosts. They provide the most extensive database on molecular recognition in the literature, with more than 100,000 publications [2]. CDs owe their success not only to the unique molecular structure [3], which allows them to act as host compounds, but also to

Bromination of endo-7-norbornene derivatives revisited: failure of a computational NMR method in elucidating the configuration of an organic structure

• Demet Demirci Gültekin,
• Arif Daştan,
• Yavuz Taşkesenligil,
• Cavit Kazaz,
• Yunus Zorlu and
• Metin Balci

Beilstein J. Org. Chem. 2023, 19, 764–770, doi:10.3762/bjoc.19.56

• ppm). NOE-Diff experiment. Irradiation at the resonance frequency of proton H7 (4.23 ppm). A) Molecular structure of the compound 6 with displacement ellipsoids drawn at the 30% probability level. H-atoms are shown as small spheres of arbitrary radii. B) Perspective view of the crystal packing of

Synthesis, structure, and properties of switchable cross-conjugated 1,4-diaryl-1,3-butadiynes based on 1,8-bis(dimethylamino)naphthalene

• Semyon V. Tsybulin,
• Ekaterina A. Filatova,
• Alexander F. Pozharskii,
• Valery A. Ozeryanskii and
• Anna V. Gulevskaya

Beilstein J. Org. Chem. 2023, 19, 674–686, doi:10.3762/bjoc.19.49

• ). Molecular structure of compound 11c: frontal (top; BF4− omitted) and side views (bottom; hydrogen atoms omitted). Calculation of the qr parameter. Two π-conjugation ways in oligomers 5. UV–vis spectra of oligomers 5 (blue line), monomers 6 (red line), and butadiyne 1 (green line). UV–vis spectra of salts 11

Combining the best of both worlds: radical-based divergent total synthesis

• Kyriaki Gennaiou,
• Antonios Kelesidis,
• Maria Kourgiantaki and
• Alexandros L. Zografos

Beilstein J. Org. Chem. 2023, 19, 1–26, doi:10.3762/bjoc.19.1

• libraries. But how big should this chemical space be, so as to actually address our needs? A general consensus has emerged, supporting that “it is not actually the library size but rather the library diversity in terms of molecular structure and function which is fundamental for a successful drug discovery

Redox-active molecules as organocatalysts for selective oxidative transformations – an unperceived organocatalysis field

• Elena R. Lopat’eva,
• Igor B. Krylov,
• Dmitry A. Lapshin and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2022, 18, 1672–1695, doi:10.3762/bjoc.18.179

• recent years are covered here. The present article is aimed at the summarization of main molecular structure types employed in redox organocatalysis, the consolidation of this research field, and highlighting possible areas of further development. Discussion The present article is aimed at the

Rhodium-catalyzed intramolecular reductive aldol-type cyclization: Application for the synthesis of a chiral necic acid lactone

• Motoyuki Isoda,
• Kazuyuki Sato,
• Kenta Kameda,
• Kana Wakabayashi,
• Ryota Sato,
• Hideki Minami,
• Yukiko Karuo,
• Atsushi Tarui,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2022, 18, 1642–1648, doi:10.3762/bjoc.18.176

• monocrotaline There are several reports of bioactive natural products that have a 3-hydroxy-2-methyllactone scaffold in the molecular structure. For example, cytospolide K2 [50] containing a 10-membered lactone and feigrisolide [51] containing a 7-membered lactone are known to exhibit cytotoxicity and

• . In addition, we demonstrated a new approach to a necic acid lactone 2j that is a diastereomer of monocrotalic acid, a key intermediate of monocrotalin. Bioactive natural products bearing a 3-hydroxy-2-methyllactone scaffold. Monocrotaline and its structural components. Molecular structure of necic

Comparison of crystal structure and DFT calculations of triferrocenyl trithiophosphite’s conformance

• Ruslan P. Shekurov,
• Mikhail N. Khrizanforov,
• Ilya A. Bezkishko,
• Tatiana P. Gerasimova,
• Almaz A. Zagidullin,
• Daut R. Islamov and
• Vasili A. Miluykov

Beilstein J. Org. Chem. 2022, 18, 1499–1504, doi:10.3762/bjoc.18.157

• C–H···O interactions, respectively, are observed. It should be noted that (FcS)3PO crystals contain a solvent molecule that participates in intermolecular interactions. Thus, despite the similarity of the molecular structure of the three compounds and some crystal parameters, the intermolecular

Naphthalimide-phenothiazine dyads: effect of conformational flexibility and matching of the energy of the charge-transfer state and the localized triplet excited state on the thermally activated delayed fluorescence

• Kaiyue Ye,
• Liyuan Cao,
• Davita M. E. van Raamsdonk,
• Zhijia Wang,
• Jianzhang Zhao,
• Daniel Escudero and
• Denis Jacquemin

Beilstein J. Org. Chem. 2022, 18, 1435–1453, doi:10.3762/bjoc.18.149

• observed in the nanosecond transient absorption spectra with lifetimes in the 4–48 μs range. Computational investigations show that the orthogonal electron donor–acceptor molecular structure is beneficial for TADF. These calculations indicate small energetic difference between the 3LE and 3CT states, which

• -transfer (CT) and intersystem-crossing (ISC) phenomena [4][5]. Compounds showing TADF are usually presenting an orthogonal electron donor–acceptor molecular structure, i.e., the π-planes of the electron donor and acceptor adopt an orthogonal geometry [6][7]. Such an architecture is beneficial to spatially

Synthesis of C6-modified mannose 1-phosphates and evaluation of derived sugar nucleotides against GDP-mannose dehydrogenase

• Sanaz Ahmadipour,
• Alice J. C. Wahart,
• Jonathan P. Dolan,
• Laura Beswick,
• Chris S. Hawes,
• Robert A. Field and
• Gavin J. Miller

Beilstein J. Org. Chem. 2022, 18, 1379–1384, doi:10.3762/bjoc.18.142

• , the structural model allowed unambiguous assignment of the solid state molecular structure and absolute configuration. As shown in Figure 2, the desired axial anomeric phosphate was clearly visible alongside an interesting gg rotameric form for the C6–chloro side chain substituent (pyranose side chain

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

• subunit. View of the molecular structure of compound 10aa with atom labeling. Displacement ellipsoids are drawn at the 30% probability level. The intramolecular hydrogen bond N15–H15···O13 is shown as dashed line. The PES of reaction for the synthesis of 1,4,5-trisubstituted pyrrolidine-2,3-dione 10ab

Scope of tetrazolo[1,5-a]quinoxalines in CuAAC reactions for the synthesis of triazoloquinoxalines, imidazoloquinoxalines, and rhenium complexes thereof

• Laura Holzhauer,
• Chloé Liagre,
• Olaf Fuhr,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2022, 18, 1088–1099, doi:10.3762/bjoc.18.111

• –d and ORTEP diagrams of the resulting molecular structures with the thermal ellipsoids shown at 50% probability. Synthesis of rhenium tricarbonyl complex 29 and ORTEP diagram of the resulting molecular structure with the thermal ellipsoids shown at 50% probability. Synthesis of a TIQ rhenium complex

Thiophene/selenophene-based S-shaped double helicenes: regioselective synthesis and structures

• Mengjie Wang,
• Lanping Dang,
• Wan Xu,
• Zhiying Ma,
• Liuliu Shao,
• Guangxia Wang,
• Chunli Li and
• Hua Wang

Beilstein J. Org. Chem. 2022, 18, 809–817, doi:10.3762/bjoc.18.81

• packing structures of these compounds. Spectroscopic results and our previous work showed that the combination of molecular structure change and heteroatom replacement from S to Se could precisely modulate molecular energy levels. Keywords: crystal structure; double helicene; regioselective synthesis

• arrangement in the crystal packing structures of DH-1 and DH-2 indicate that these compounds may be used as supramolecular self-assembly units. Changes in molecular structure may substantially modulate the optical band gap of heteroacenes, and the replacement of heteroatoms from S to Se could fine-tune their

• optical band gap [18][27][28]. Thus, the combination of molecular structure modification and atom replacement could be a viable strategy, for the precise modulation molecular energy levels and yield molecules with strong application potential in organic functional materials, such as OFETs, and CPLs, among

Synthesis of bis-spirocyclic derivatives of 3-azabicyclo[3.1.0]hexane via cyclopropene cycloadditions to the stable azomethine ylide derived from Ruhemann's purple

• Alexander S. Filatov,
• Olesya V. Khoroshilova,
• Anna G. Larina,
• Vitali M. Boitsov and
• Alexander V. Stepakov

Beilstein J. Org. Chem. 2022, 18, 769–780, doi:10.3762/bjoc.18.77

• cycloadditions of tetrasubstituted azomethine ylides with cyclopropenes. ORTEP representation of the molecular structure of 3e. Early studies concerning cyclopropene cycloadditions to azomethine ylides and cycloaddition reactions involving protonated Ruhemann's purple (PRP). The pilot experiment aimed at

A trustworthy mechanochemical route to isocyanides

• Francesco Basoccu,
• Federico Cuccu,
• Federico Casti,
• Rita Mocci,
• Claudia Fattuoni and
• Andrea Porcheddu

Beilstein J. Org. Chem. 2022, 18, 732–737, doi:10.3762/bjoc.18.73

• , they are often used in heterocycles formation [8][9], multicomponent strategies [10][11], polymers production [12][13], and metal complexation [14][15]. The molecular structure is composed of an N–C planar triple bond where the nitrogen atom assumes a positive charge due to the fourth bond with a

Mechanochemical halogenation of unsymmetrically substituted azobenzenes

• Dajana Barišić,
• Mario Pajić,
• Ivan Halasz,
• Darko Babić and
• Manda Ćurić

Beilstein J. Org. Chem. 2022, 18, 680–687, doi:10.3762/bjoc.18.69

• % yields, respectively, as confirmed by NMR spectroscopy (Figures S82–S91 in Supporting Information File 1). Additional support for the formation of succinimide products was provided by the molecular structure of L4-III, resolved by single-crystal X-ray analysis (Figure 3 and Figure S33 and Table S1 in

• Supporting Information File 1). The molecular structure of L4-III showed that imidation occurred at the methyl group of the NMe2 substituent. Analogous succinimide species were also observed in the reaction of N,N-dimethyl-p-toluidine with NIS in ethyl acetate [55] or N,N-dimethylamides and N,N

• monitoring. Experimental X-ray molecular structure of succinimide product L4-III. Experimental X-ray molecular structure of the intermediate I6-I. a) In situ observation of I6-I during the time-resolved Raman monitoring of LAG of L6 (0.50 mmol) with NBS (0.6 mmol), TsOH (0.25 mmol), Pd(OAc)2 (30 mol %), MeCN

Substituent effect on TADF properties of 2-modified 4,6-bis(3,6-di-tert-butyl-9-carbazolyl)-5-methylpyrimidines

• Irina Fiodorova,
• Tomas Serevičius,
• Rokas Skaisgiris,
• Saulius Juršėnas and
• Sigitas Tumkevicius

Beilstein J. Org. Chem. 2022, 18, 497–507, doi:10.3762/bjoc.18.52

• .18.52 Abstract The interest in organic materials exhibiting thermally activated delayed fluorescence (TADF) significantly increased in recent years owing to their potential application as emitters in highly efficient organic light emitting diodes (OLEDs). Simple modification of the molecular structure

• modified with various phenyl-like fragments, increasing the flexibility of the molecular structure, probably altering the electron–vibronic coupling. A similar behavior was observed for similar pyrimidine TADF compounds [42]. Moreover, fluorescence line shapes of compounds 2a and 2d were different from the

Synthesis and bioactivity of pyrrole-conjugated phosphopeptides

• Qiuxin Zhang,
• Weiyi Tan and
• Bing Xu

Beilstein J. Org. Chem. 2022, 18, 159–166, doi:10.3762/bjoc.18.17

• spacer in the molecular structure. As the enantiomers of 2g and 2h, respectively, 3a and 3b offer an opportunity to assess the effects of stereochemistry of the pyrrole-capped phosphopeptides. Substituting the ᴅ-phosphotyrosine (py) in 2g and 2h, by ᴅ-phosphoserine (ps), affords 4a and 4b, respectively

Effect of a twin-emitter design strategy on a previously reported thermally activated delayed fluorescence organic light-emitting diode

• Ettore Crovini,
• Zhen Zhang,
• Yu Kusakabe,
• Yongxia Ren,
• Yoshimasa Wada,
• Bilal A. Naqvi,
• Prakhar Sahay,
• Tomas Matulaitis,
• Stefan Diesing,
• Ifor D. W. Samuel,
• Wolfgang Brütting,
• Katsuaki Suzuki,
• Hironori Kaji,
• Stefan Bräse and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2021, 17, 2894–2905, doi:10.3762/bjoc.17.197

• vertical orientation of its TDM are the primary factors governing the relatively poorer device performance, with an EQEmax of 8.4%, compared to the vacuum-deposited OLED with ICzTRZ [14]. Molecular structures of emitters. a) Molecular structure and b) optimized DFT-calculated geometry of DICzTRZ. Hydrogen

Photophysical, photostability, and ROS generation properties of new trifluoromethylated quinoline-phenol Schiff bases

• Inaiá O. Rocha,
• Yuri G. Kappenberg,
• Wilian C. Rosa,
• Clarissa P. Frizzo,
• Nilo Zanatta,
• Marcos A. P. Martins,
• Isadora Tisoco,
• Bernardo A. Iglesias and
• Helio G. Bonacorso

Beilstein J. Org. Chem. 2021, 17, 2799–2811, doi:10.3762/bjoc.17.191

• solution and no signal belonging to the Z isomer was observed in all cases, which can be confirmed by the chemical shift values in the 1H NMR regarding the –CH=N bond. Finally, in order to determine the real molecular structure of the Schiff bases 3, single-crystal X-ray diffraction (SC-XRD) was performed