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

• synthesized by other methods and the single Suzuki reaction on uracil is well studied [42][69][70][71]. Physical properties The photophysical properties of selected derivatives were investigated by steady-state absorption and photoluminescence spectroscopy. The influence of the substitution pattern on the

• photophysical properties is displayed in Figure 4. Corresponding photophysical data and quantum yields are described in Table 2. The analysis of the absorption spectra revealed that the spectra can be divided into a short-wave and long-wave region. In the long wavelength region (350–500 nm) all measured

• gives first insights into the optical properties. It was observed that the photophysical properties could be partially modulated by the chosen substituents. Experimental General information Nuclear magnetic resonance spectra (1H/13C/19F NMR) were recorded on a Bruker AVANCE 300 III, 250II, or 500. The

Switchable molecular tweezers: design and applications

• Pablo Msellem,
• Maksym Dekthiarenko,
• Nihal Hadj Seyd and
• Guillaume Vives

Beilstein J. Org. Chem. 2024, 20, 504–539, doi:10.3762/bjoc.20.45

Mono or double Pd-catalyzed C–H bond functionalization for the annulative π-extension of 1,8-dibromonaphthalene: a one pot access to fluoranthene derivatives

• Nahed Ketata,
• Linhao Liu,
• Ridha Ben Salem and
• Henri Doucet

Beilstein J. Org. Chem. 2024, 20, 427–435, doi:10.3762/bjoc.20.37

• ; palladium; Introduction Substituted polyaromatics such as fluoranthenes (Figure 1) are widely used in materials chemistry due to their physical properties, and the introduction of a suitable functional group on the appropriate positions of fluoranthenes either allows their photophysical properties to be

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

• towards indigo and its derivatives have been recently reviewed in detail by Hecht and Huang [9]. Strucutre and photophysical properties of indigo Indigo dye is blue crystalline powder, which starts to melt at above 390 °C and sublimes in vacuum at above 170 °C [2]. In 1980, it was discovered that indigo

• interest and, therefore, has been investigated comprehensively. To understand the photochemical and photophysical properties of indigo, a great number of theoretical and experimental studies [25][26][27][28][29][30][31][32][33][34][35] have been performed so far, which allowed to characterize excited state

• accelerated in the presence of acid. In 2017 and 2022, Hecht, Jacquemin and co-workers successfully synthesized a range of N,N'-disubstituted indigos, including N,N'-dialkyl derivatives, using novel approaches and investigated their photophysical properties, in particular, the thermal half-lives and the ratio

Perspectives on push–pull chromophores derived from click-type [2 + 2] cycloaddition–retroelectrocyclization reactions of electron-rich alkynes and electron-deficient alkenes

• Michio Yamada

Beilstein J. Org. Chem. 2024, 20, 125–154, doi:10.3762/bjoc.20.13

• particular, Diederich et al. conducted a theoretical investigation on the photophysical properties of 1,1,2,4,4-pentacyanobuta-1,3-diene (PCBD) (63) [134]. Compound 63 and the TCBD 64 demonstrated no discernible luminescence at room temperature and 77 K (Figure 4). Transient absorption spectral measurements

• . Concurrently, the excited electron was extensively delocalized over the entire pentacyanobutadiene moiety. The researchers postulated the following description for the photophysical properties of 64: a nonradiative deactivation process occurred via a CI, which was similar to that observed in the case of 63

• TCBD, donor–acceptor conjugated systems have been systematically developed by coupling the TCBD motif with an electron donor, resulting in the experimental observation of photoinduced electron- and energy-transfer events. In 2014, comprehensive investigations on the photophysical properties of

Biphenylene-containing polycyclic conjugated compounds

• Cagatay Dengiz

Beilstein J. Org. Chem. 2023, 19, 1895–1911, doi:10.3762/bjoc.19.141

• 616 nm. Based on the photophysical properties of compounds 54a and 54b, which were synthesized in the previous study (Scheme 11), it is evident that the addition of the second biphenylene-fused pyrazine group to the structure leads to a substantial red shift towards the NIR region. This observation

• not be separated by physical methods, it was not possible to study their photophysical properties separately. Nonetheless, comparison of the properties of POAs 73 and 84 has provided essential data. Closely resembling compound 73, the red color of POA 84 is attributed to an extensively broad

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

• compounds. In general, polyaromatic π-systems with pyridine-3,5-dicarbonitrile fragments demonstrate promising potential for use in organic electronic devices, such as OLEDs. Keywords: charge transport; intramolecular charge transfer; photophysical properties; pyridine-3,5-dicarbonitrile; Introduction The

• of pyridine-3,5-dicarbonitrile-derived electron-acceptor and acridine electron–donor moieties. The films of molecular mixtures of these emitters with the hosts exhibited excellent photophysical properties [6]. They showed PLQY of up to 91%, tiny singlet–triplet energy gaps of 0.01 eV, and ultrashort

• compounds 6–9 were confirmed by the spectral data and elemental analyses. Remarkably, despite a highly hindered structure, compound 9 exhibits good solubility in non-polar solvents. Photophysical properties The electronic structures of compounds 6–9 in the ground and excited states were investigated by

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

• pull–push fluorophore, DMB-TT-TPA (8), having TPA and DMB units as donor and acceptor units that were linked through a 4-MeOPh-substituted TT core as a π-spacer. The photophysical properties of the fluorophore were investigated by spectroscopic methods. Moreover, DMB-TT-TPA (8) was fabricated as an

• emitter for an organic light-emitting diode through a solution process. DMB-TT-TPA (8) displayed excellent performance in both device application and photophysical properties, i.e., a maximum solution fluorescence quantum yield of 86% in THF, maximum solid-state fluorescence quantum yield of 41%, maximum

• lithiation of 7 and following reaction with dimesitylboron fluoride in 85% yield (Scheme 1). Photophysical properties The UV–vis absorption and fluorescence spectra of DMB-TT-TPA (8) were recorded in THF (Figure 1 and Table 1) [38]. It showed maximum absorption and emission wavelengths of 411 and 520 nm

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

• of Their Photophysical Properties” written by Seda Cinar, Hacettepe University, Graduate School of Science and Engineering, Beytepe Campus, 06800, Ankara, Turkey. Funding SC thanks The Scientific and Technological Research Council of Turkey (TUBITAK) for doctoral scholarship (2211-C Domestic Ph.D

A deep-red fluorophore based on naphthothiadiazole as emitter with hybridized local and charge transfer and ambipolar transporting properties for electroluminescent devices

• Suangsiri Arunlimsawat,
• Patteera Funchien,
• Pongsakorn Chasing,
• Atthapon Saenubol,
• Taweesak Sudyoadsuk and
• Vinich Promarak

Beilstein J. Org. Chem. 2023, 19, 1664–1676, doi:10.3762/bjoc.19.122

• luminescence efficiency, while a significant spatial separation between hole and particle wavefunctions considered for CT component promoting RISC process along high-lying excitation state for enhancing an exciton utilization efficiency (EUE). The photophysical properties of TPECNz were studied in solution

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

• supramolecular architectures [45], e.g., catenanes [73], rotaxanes [74], and catalytic systems [75]. Pelegrino and co-workers reported on crowned porphyrinoids demonstrating interesting photophysical properties [71]. The crown ether part was also demonstrated to play a role of a linker between two porphyrin

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

• directly related with the overlap integral between HOMO and LUMO orbitals and influences the energy differences between first singlet and triplet excited states [14]. Therefore, we expect a marked difference in the photophysical properties for 4BGIPN, vide infra. Analysis of the intermolecular interactions

• and LUMO energy levels indicates the potential suitability of 4BGIPN material for application not only as emitter in the emitting layer but also as an electron transport layer in the fabrication of OLEDs. Photophysical properties and theoretical considerations UV–vis and photoluminescence (PL) spectra

• and 4CzIPN [15][17] in various solvents. Photophysical properties of 4BGIPN in various media at 296 and 77 K. Supporting Information Supporting Information File 151: Additional experimental data. Supporting Information File 152: CIF file. Acknowledgements We are grateful to ZEON EUROPE GmbH for

New one-pot synthesis of 4-arylpyrazolo[3,4-b]pyridin-6-ones based on 5-aminopyrazoles and azlactones

• Vladislav Yu. Shuvalov,
• Ekaterina Yu. Vlasova,
• Tatyana Yu. Zheleznova and
• Alexander S. Fisyuk

Beilstein J. Org. Chem. 2023, 19, 1155–1160, doi:10.3762/bjoc.19.83

• -aminopyrazoles 1, 5, 6 and azlactones 2a–i, followed by heating the resulting intermediate in DMSO in the presence of t-BuOK. Photophysical properties of the obtained compounds were studied. Biologically active 4-arylpyrazolo[3,4-b]pyridin-6-ones. Normalized absorption and fluorescence spectra of solutions of

Photoredox catalysis harvesting multiple photon or electrochemical energies

• Mattia Lepori,
• Simon Schmid and
• Joshua P. Barham

Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81

• cyclized product 5a was obtained – albeit only in 28% yield – corroborating a radical mechanism. PDI catalysts have since found applications in other chemical transformations, their photophysical properties have been investigated further [40], and new variants [41] including heterogeneous versions have

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

• –acceptor dyads were prepared to study the thermally activated delayed fluorescence (TADF) properties of the dyads, from a point of view of detection of the various transient species. The photophysical properties of the dyads were tuned by changing the electron-donating and the electron-withdrawing

• structures is the alkyl chain, we called that analogue NI-PTZ-N here) [39]. In order to study the effect of tuning the energy and the ordering of the excited states on the photophysical properties of the dyad, especially the ISC and TADF properties, we introduced electron-donating and -withdrawing aryl

• analogous dyads, however, their molecular structures are different from the current dyads, and the photophysical properties were tuned by variation of the distance between the NI and the PTZ units, or by oxidation of the PTZ unit [47]. In the current dyads, we used different strategies. A commonly used

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

• exploit three-dimensional aesthetic structures. The continuously developed novel structures contented our interests and curiosity. To further tune the optoelectronic or photophysical properties of nanographenes for real applications, heteroatom doping was found to be an effective strategy. The

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

• % yield. Furthermore, this zinc conjugate was demetallated using H3PO4 in THF to form the free-base porphyrin 148b in 90% yield. The photophysical properties of this dendronized porphyrin molecule was investigated by absorption and fluorescence spectroscopy in different solvents, and the amphiphilic

• molecular architectures featuring 1,4-disubstituted triazole units with high yield and higher regioselectivity. The click-inspired synthesis and photophysical properties of diverse triazole-linked porphyrin conjugates are discussed in this review. This review includes a number of recent and important

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

• -PTZ) [36]. The electronic coupling between the NI and PTZ units differ these two dyads. Finally, in NI-PhMe2-PTZ with methyl substituents, the phenyl linker adopts an orthogonal geometry with respect to the NI moiety, inducing a weaker coupling than that in NI-Ph-PTZ. The photophysical properties of

• from that of NI-PTZ, and the CT absorption band centered at 423 nm is much more intense than that of NI-PTZ, indicating that the electronic effect of the substituents does not have a simple additive effect on the photophysical properties [42]. The CT absorption band of NI-PTZ-O is much weaker

• characteristic TADF lifetimes (Figure 4b and 4e). Clearly, besides the conformational flexibility, other factors do play a role in the photophysical properties of the dyad, i.e., the magnitudes of CT/3LE energy gap, and related spin–vibronic couplings. Increasing the CT state energy either through oxidation of

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

• 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

Ionic multiresonant thermally activated delayed fluorescence emitters for light emitting electrochemical cells

• Merve Karaman,
• Abhishek Kumar Gupta,
• Subeesh Madayanad Suresh,
• Tomas Matulaitis,
• Lorenzo Mardegan,
• Daniel Tordera,
• Henk J. Bolink,
• Sen Wu,
• Stuart Warriner,
• Ifor D. Samuel and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2022, 18, 1311–1321, doi:10.3762/bjoc.18.136

• line with the DFT calculations. Figure 3b shows the solution-state photophysical properties of DiKTa-OBuIm and DiKTa-DPA-OBuIm in acetonitrile and the data are compiled in Table 1. The lowest energy absorption band for DiKTa-OBuIm at 453 nm (ε = 17 × 103 M−1 cm−1) is red-shifted and slightly more

• both emitters was then assessed in 1 wt % doped film in 1,3-di-9-carbazolylbenzene (mCP) (Figure 4). At this doping concentration, the photophysical properties should reflect monomolecular entities. Emission was observed at 500 nm (FWHM = 66 nm) and 578 nm (FWHM = 95 nm) for DiKTa-OBuIm and DiKTa-DPA

• in DiKTa-OBuIm. Synthesis of DiKTa-OBuIm and DiKTa-DPA-OBuIm. Photophysical properties of DiKTa-OBuIm and DiKTa-DPA-OBuIm. Supporting Information The research data supporting this publication can be accessed at https://doi.org/10.17630/6ef45b8f-579d-4075-891e-595516c56e47. Supporting Information

Thermally activated delayed fluorescence (TADF) emitters: sensing and boosting spin-flipping by aggregation

• Ashish Kumar Mazumdar,
• Gyana Prakash Nanda,
• Nisha Yadav,
• Upasana Deori,
• Upasha Acharyya,
• Bahadur Sk and
• Pachaiyappan Rajamalli

Beilstein J. Org. Chem. 2022, 18, 1177–1187, doi:10.3762/bjoc.18.122

• splitting was observed for BPy-p3C (ΔEST = 0.047 eV) as compared to BPy-pTC (ΔEST = 0.121 eV) due to the twisted molecular geometry (Figure 1 and Table 1). The small ΔEST values indicated a possible RISC process from the T1 to the S1 state for both the compounds. The photophysical properties of both the

• (d) BPy-p3C in toluene solution. Fluorescence intensity vs number of exposures for (a) BPy-p3C and (b) BPy-pTC thin films upon exposure to TFA and TEA vapors. Synthetic schemes of BPy-pTC and BPy-p3C. Photophysical properties of BPy-pTC and BPy-p3C.a Photophysical properties of BPy-pTC and BPy-p3C

Syntheses of novel pyridine-based low-molecular-weight luminogens possessing aggregation-induced emission enhancement (AIEE) properties

• Masayori Hagimori,
• Tatsusada Yoshida,
• Yasuhisa Nishimura,
• Yukiko Ogawa and
• Keitaro Tanaka

Beilstein J. Org. Chem. 2022, 18, 580–587, doi:10.3762/bjoc.18.60

• aminopyridines based on the acceptor–donor–acceptor (A–D–A) system exhibit AIEE properties in aqueous media, which may be novel candidate molecules for AIEE. Herein, we report the synthesis, photophysical properties, and computational studies of pyrido[1,2-a]pyrrolo[3,4-d]pyrimidines and N-methyl-4-((pyridin-2

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

• and 100 MHz for 1H and 13C, respectively). 1H NMR and 13C NMR spectra were referenced to residual solvent peaks. High-resolution mass spectrometry (HRMS) analyses were carried out on a Dual-ESI Q-TOF 6520 (Agilent Technologies) mass spectrometer. Photophysical properties were analyzed in 10−5 M

• computed S0→S1/T1 transition energies, oscillator strengths of S0→S1 transitions, and ΔEST values of carbazole–pyrimidine TADF compounds. Fluorescence parameters of carbazole–pyrimidine TADF compounds. Supporting Information Supporting Information File 44: Copies of NMR spectra and extended photophysical

• properties.

Comparative study of thermally activated delayed fluorescent properties of donor–acceptor and donor–acceptor–donor architectures based on phenoxazine and dibenzo[a,j]phenazine

• Saika Izumi,
• Prasannamani Govindharaj,
• Anna Drewniak,
• Paola Zimmermann Crocomo,
• Satoshi Minakata,
• Leonardo Evaristo de Sousa,
• Piotr de Silva,
• Przemyslaw Data and
• Youhei Takeda

Beilstein J. Org. Chem. 2022, 18, 459–468, doi:10.3762/bjoc.18.48

• ) compound based on a donor–acceptor (D–A) architecture (D = phenoxazine; A = dibenzo[a,j]phenazine) has been developed, and its photophysical properties were characterized. The D–A compound is applicable as an emitting material for efficient organic light-emitting diodes (OLEDs), and its external quantum

• compound 1 was fully characterized by 1H and 13C NMR and IR spectroscopy, MS spectrometry as well as elemental analysis (for the detailed data, see Supporting Information File 1). Steady-state PL spectra To reveal the photophysical properties of diluted solutions of compound 1, UV–vis absorption and steady

• for generating the CT excited state. In comparison with the photophysical properties of the D–A–D compound, the absorption of 1 (λabs = 461 nm) is almost the same as that of POZ-DBPHZ (λabs = 463 nm) [17], while the PL emission peak appeared in a slightly blue-shifted region (λPL = 502 nm) from D–A–D

1,2-Naphthoquinone-4-sulfonic acid salts in organic synthesis

• Ruan Carlos B. Ribeiro,
• Patricia G. Ferreira,
• Amanda de A. Borges,
• Luana da S. M. Forezi,
• Fernando de Carvalho da Silva and
• Vitor F. Ferreira

Beilstein J. Org. Chem. 2022, 18, 53–69, doi:10.3762/bjoc.18.5

• quinoid type to study their photophysical properties in solution and in the solid-state, Ooyama and co-workers [106] studied a synthetic route for the preparation of compounds with the tricyclic benzo[c]carbazol-6-one skeleton. The strategy used was through the reaction to β-NQS 18 with a bifunctional