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

• quinone unit on quinoxaline to achieve donor–acceptor interactions and desirable electronic properties. The compounds exhibited absorption, emission, electrochemical, and thermal properties suitable for n-type materials. Theoretical properties were also investigated using time-dependent DFT. The HOMO and

Mesoionic tetrazolium-5-aminides: Synthesis, molecular and crystal structures, UV–vis spectra, and DFT calculations

• Vladislav A. Budevich,
• Sergei V. Voitekhovich,
• Alexander V. Zuraev,
• Vadim E. Matulis,
• Vitaly E. Matulis,
• Alexander S. Lyakhov,
• Ludmila S. Ivashkevich and
• Oleg A. Ivashkevich

Beilstein J. Org. Chem. 2021, 17, 385–395, doi:10.3762/bjoc.17.34

• delocalized into vicinal N2–N3* and C5–N5* antibonds, leading to the Lewis structures B and C, correspondingly (Scheme 3). A similar analysis of donor–acceptor interactions for the obtained structures leads to the Lewis structures D and E. Note that the structures B and D with a C5–N5 double bond have only a

Polarity effects in 4-fluoro- and 4-(trifluoromethyl)prolines

• Vladimir Kubyshkin

Beilstein J. Org. Chem. 2020, 16, 1837–1852, doi:10.3762/bjoc.16.151

• substitution of proline with analogues can result in the conformational stabilization and polarity effects competing with each other [58]. Finally, it has been shown that fluoroprolines can alter donor–acceptor interactions of the proline ring with a tryptophan residue [59]. All these findings indicate that

Conformational signature of Ishikawa´s reagent using NMR information from diastereotopic fluorines

• Laize A. F. Andrade,
• Lucas A. Zeoly,
• Rodrigo A. Cormanich and
• Matheus P. Freitas

Beilstein J. Org. Chem. 2019, 15, 506–512, doi:10.3762/bjoc.15.44

• natural bond orbital (NBO) [34] analyses at the ωB97X-D/6-311++G(d,p) level [31][32] were performed to obtain the second-order perturbation energies of donor–acceptor interactions. This same level of theory was employed for the chemical shift and SSCC calculations. Structure of Ishikawa´s reagent (1) and

Tetrathiafulvalene – a redox-switchable building block to control motion in mechanically interlocked molecules

• Hendrik V. Schröder and
• Christoph A. Schalley

Beilstein J. Org. Chem. 2018, 14, 2163–2185, doi:10.3762/bjoc.14.190

• for a non-charged TTF-based rotaxane was reported in 2011 (Figure 14) [81]. Very similar to the prior bistable rotaxanes, donor–acceptor interactions dominate the relation of wheel and axle in [2]rotaxane 16. Here, a π-electron-deficient pyromellitic diimide macrocycle encircles a TTF station (Ka

• Figure 27b), donor–acceptor interactions and hydrogen bonding generate a neutral TTF dimer that is surrounded by cofacially oriented bipyridinium units [112]. The intertwined structure is locked by formation of platinum(II)–pyridine coordination bonds. Interestingly, the doubly interlocked catenane

Preparation and X-ray structure of 2-iodoxybenzenesulfonic acid (IBS) – a powerful hypervalent iodine(V) oxidant

• Irina A. Mironova,
• Pavel S. Postnikov,
• Rosa Y. Yusubova,
• Akira Yoshimura,
• Thomas Wirth,
• Viktor V. Zhdankin,
• Victor N. Nemykin and
• Mekhman S. Yusubov

Beilstein J. Org. Chem. 2018, 14, 1854–1858, doi:10.3762/bjoc.14.159

• . In addition, a water molecule was observed in the crystal structure of 6, which forms two strong hydrogen bonds (≈2.05 Å for O(21)–H(2)···O(11) and ≈2.07 Å for O(21)–H(3)···O(5)) with neighbouring oxygen atoms and two short donor–acceptor interactions with K(1) and K(2) potassium ions. Overall, the

p-tert-Butylthiacalix[4]arenes functionalized by N-(4’-nitrophenyl)acetamide and N,N-diethylacetamide fragments: synthesis and binding of anionic guests

• Alena A. Vavilova and
• Ivan I. Stoikov

Beilstein J. Org. Chem. 2017, 13, 1940–1949, doi:10.3762/bjoc.13.188

• negatively charged substrates. Usually, receptors for anions are charged systems capable of electrostatic interaction with anions [1][44][45] or neutral systems using other types of interactions, such as donor–acceptor interactions, hydrogen bonds, hydrophobic effects, etc. [46][47][48][49][50][51][52][53

Polythiophene and oligothiophene systems modified by TTF electroactive units for organic electronics

• Alexander L. Kanibolotsky,
• Neil J. Findlay and
• Peter J. Skabara

Beilstein J. Org. Chem. 2015, 11, 1749–1766, doi:10.3762/bjoc.11.191

• from those in solution (−4.95/−3.55 eV), which suggested significant donor–acceptor interactions in the solid phase between the DPP and TTF units. OFET device fabrication employing polymer 48 exhibited p-type semiconductor behaviour, with the best performance from devices using the bottom contact top

• dithienyl-thieno-TTF unit and the localised nature of the LUMO led to donor–acceptor interactions in the solid phase, making it impossible for efficient overlap between LUMOs, which would normally be required for an efficient n-type semiconductor. BHJSCs were fabricated from 48 as the electron donor and

Donor–acceptor type co-crystals of arylthio-substituted tetrathiafulvalenes and fullerenes

• Xiaofeng Lu,
• Jibin Sun,
• Shangxi Zhang,
• Longfei Ma,
• Lei Liu,
• Hui Qi,
• Yongliang Shao and
• Xiangfeng Shao

Beilstein J. Org. Chem. 2015, 11, 1043–1051, doi:10.3762/bjoc.11.117

• surrounded by six C70 neighbors. Along the longitudinal and lateral axes of molecule 2, four A molecules are located to show multiple donor–acceptor interactions (Figure 4a): C–C contacts (3.22–3.37 Å) between p-tolyl moieties and C70 along the longitudinal axis of 2, and C–S contacts (3.44, 3.47Å) between

• plays a significant role on the donor–acceptor interaction mode and the packing motif of the fullerenes. In the type I co-crystals (D:A = 1:1), the donor–acceptor interactions mainly exist between the central TTF core of the Ar-S-TTF and the fullerene molecules. Therefore, Ar-S-TTF serves as the host

Glycoluril–tetrathiafulvalene molecular clips: on the influence of electronic and spatial properties for binding neutral accepting guests

• Yoann Cotelle,
• Marie Hardouin-Lerouge,
• Stéphanie Legoupy,
• Olivier Alévêque,
• Eric Levillain and
• Piétrick Hudhomme

Beilstein J. Org. Chem. 2015, 11, 1023–1036, doi:10.3762/bjoc.11.115

• control binding interaction towards a strong electron acceptor such as tetrafluorotetracyanoquinodimethane (F4-TCNQ) or a weaker electron acceptor such as 1,3-dinitrobenzene (m-DNB). Keywords: donor–acceptor interactions; glycoluril; molecular clips; supramolecular chemistry; tetrathiafulvalene

• through an induced-fit mechanism with a recognition process on the basis of the size rather than the acceptor strength. We can suppose that the presence of stronger π-donor TTF sidewalls in clip 3 favorize donor–acceptor interactions and consequently the binding properties towards m-DNB. We have also

Conformational analysis of 2,2-difluoroethylamine hydrochloride: double gauche effect

• Josué M. Silla,
• Claudimar J. Duarte,
• Rodrigo A. Cormanich,
• Roberto Rittner and
• Matheus P. Freitas

Beilstein J. Org. Chem. 2014, 10, 877–882, doi:10.3762/bjoc.10.84

• perturbation analysis of donor-acceptor interactions in the natural bond orbitals (NBOs) framework shows that the global minimum of 1 is more stabilized by hyperconjugation than the other conformers (both in the gas phase and implicit water), despite being significantly destabilized by Lewis-type interactions

Conformational analysis and intramolecular interactions in monosubstituted phenylboranes and phenylboronic acids

• Josué M. Silla,
• Rodrigo A. Cormanich,
• Roberto Rittner and
• Matheus P. Freitas

Beilstein J. Org. Chem. 2013, 9, 1127–1134, doi:10.3762/bjoc.9.125

• goals, NMR spectroscopy (by means of suitable coupling constants) and theoretical calculations were used. Second-order perturbation analysis of donor–acceptor interactions in the natural bond orbitals (NBO) was used to interpret conformational isomerism in terms of hyperconjugative interactions, in such

Conjugated polymers containing diketopyrrolopyrrole units in the main chain

• Bernd Tieke,
• A. Raman Rabindranath,
• Kai Zhang and
• Yu Zhu

Beilstein J. Org. Chem. 2010, 6, 830–845, doi:10.3762/bjoc.6.92

• arylamine units in the main chain. Due to presence of electron-rich nitrogen atoms it was hoped that donor-acceptor interactions along the main chain would be enhanced and lead to a red-shift of the absorption and emission. Furthermore, the presence of easily oxidizable nitrogen in the main chain should