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

• photoproducts 3a–c under the influence of irradiation was developed. We applied a modified procedure using a Sweko IP65 LED emitter that had been previously developed in our studies for similar tasks [30]. For this purpose, a suspension of a yellow solid 2a–c in acetonitrile was boiled for 10–15 s and then

• irradiated with an emitter for 3–5 min. This process was repeated up to 10 times until complete dissolution had occurred. The colorless solids 3a (80%), 3b (75%) and 3c (85%), respectively, gradually precipitated. For the first time in the course of studying N→O acylotropic migrations, photorearrangement

• )methyl)-N-phenylacetamide was used as an actinometer for the quantum yield calculations (φfl = 0.60 ± 0.005) [14][33]. For preparative purposes, a Sweko IP65 led emitter (SUL-S1-20W-230-4000K-WH) was used. Spectral-fluorescent experiments were performed using solutions in acetonitrile or DMSO in quartz

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

• emitter based on a pyridine-3,5-dicarbonitrile scaffold (to serve as an electron acceptor) directly linked to a carbazole moiety (to serve as an electron donor) was reported by the groups of Dong and Zhang in 2015 [4]. 2,6-Di(9H-carbazol-9-yl)-4-phenylpyridine-3,5-dicarbonitrile (CPC) showed an extremely

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

• triphenylamine as donor and dimesitylboron as acceptor linked through a thieno[3,2-b]thiophene (TT) π-conjugated linker bearing a 4-MeOPh group, was designed, synthesized, and fabricated as an emitter via a solution process for an organic light-emitting diode (OLED) application. DMB-TT-TPA (8) exhibited

• 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

• model and synthesized in 85% yield. Its photophysical properties were investigated by UV–vis and fluorescence spectroscopy. The obtained experimental results were found to be in good agreement with computational investigations. An OLED fabrication, where DMB-TT-TPA (8) was employed as an emitter, showed

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

• indicated efficient charge transfer and exciton formation within the molecule, leading to red emission. The achieved EQE of 7.4% highlighted the potential application of this Qx-based TADF emitter as dopant in red-emitting OLED devices [65]. Huang et al. developed two yellow TADF emitters, Qx67 and Qx68

• , based on 6-(trifluoromethyl)quinoxaline or 6-cyanoquinoxaline acceptors, respectively. The small energy splitting values (0.03–0.04 eV) and long fluorescence lifetimes (5.0 μs) indicated efficient TADF processes. The utilization of these emitters in full-TADF white OLEDs, along with a sky-blue emitter

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

• –donor (D–A–D)-type molecule and its application as a non-doped emitter in an organic light-emitting diode (OLED). The fluorophore TPECNz contains naphtho[2,3-c][1,2,5]thiadiazole (Nz) as a strong acceptor unit symmetrically functionalized with N-(4-(1,2,2-triphenylvinyl)phenyl)carbazole as a donor and

• ambipolar charge-carrier-transporting property with a decent balance of mobility of electrons (1.50 × 10−5 cm2 V−1 s−1) and holes (4.42 × 10−6 cm2 V−1 s−1). TPECNz is successfully employed as a non-doped emitter in an OLED which displays deep red electroluminescent emission peaked at 659 nm with CIE

• loss through the vibronic coupling natures of the DR/NIR fluorophores [53]. As a result, TPECNz effectively possesses a strong deep-red emission with combined HLCT, weak AIE, and ambipolar transporting properties, which enabled its application as non-doped emitter. The TPECNz-based non-doped deep-red

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

• nitrogen-rich 4BGIPN material has a significantly stabilized highest occupied molecular orbital (HOMO) at −6.4 eV while the lowest unoccupied molecular orbital (LUMO) at −4.0 eV, indicating potential suitability for application as the electron transport layer or TADF class III emitter in OLEDs. Keywords

• compete with classic phosphorescent emitters that employ scarce metals such as iridium and platinum [7][8][9]. Since its first report in 2012 by Uoyama et al., 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN) has been a benchmark TADF emitter due to its high quantum yields and excellent

• 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

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

• TADF emitter 2CzPN with imidazolium groups [16][17] (Figure 1a). The LEEC devices showed a maximum external quantum efficiency (EQEmax) of 0.39%, a maximum brightness (Bmax) of 13 cd m−2, and a peak electroluminescence (λEL) at 538 nm. The device performance suffered when the emissive layer was doped

• with an ionic liquid (EQEmax = 0.12%, Bmax = 10 cd m−2), which was incorporated to increase charge mobility within the emissive layer. We later showed that this emitter could act as host material in combination with a cyanine dye emitter [18]. The EQEmax for this host–guest device was higher than for

• the non-doped device, at 2.0% demonstrated 100% exciton utilization efficiency in the device and efficient energy transfer from the host to the guest cyanine emitter. Deep blue emission in LEECs is challenging. We also reported a blue-emitting LEEC employing a cationic sulfone-based donor–acceptor

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

• donor size and strength: the emitter BPy-pTC with tert-butylcarbazole (TC) as the donor and BPy-p3C with bulky tricarbazole (3C) as the donor unit. Both BPy-pTC and BPy-p3C exhibited prominent emission with TADF properties in solution and in the solid phase. The stronger excited-state charge transfer

• detecting organic acid vapor at ambient conditions is challenging for solid-state detectors. Therefore, developing a solid-state emitter with reversible switching of the optical properties by external stimuli, such as acid and base vapors, is important. As per the recent literature, such sensors are being

• disruption of the molecular conjugation or ICT interactions upon protonation or deprotonation would lead to switching of the optical properties. While there are many reports on acid–based sensors, TADF emitter-based sensors are rare in the literature. In this context, we chose the D–A molecular design to

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

• ]. Moreover, the number and nature of various side units on the emitter framework can also affect the properties of TADF compounds [3]. Among the electron-donating units, 9,10-dihydroacridine, carbazole or phenoxazine derivatives often are used as D units, while the π-electron-deficient nitrogen heterocycles

• modified with various substituents in position 2 of the pyrimidine ring (Figure 1). For comparison, analysis of the TADF properties of a similar pyrimidine–carbazole emitter tCbz-mPYR is also included in this paper [29]. To enhance the electron-accepting character of the pyrimidine moiety some electron

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

• allow for achieving a very high external quantum efficiency (EQE) of OLEDs without using precious metals such as Ir and Pt in the emitter. Thus, the development of TADF-active organic compounds, the establishment of materials design through systematic structure–property relationship (SPR), and the

• asymmetric D–A structure. Herein, we report the synthesis of a new asymmetric D–A compound 1 (Figure 1) as a TADF emitter and its detailed physical properties. Moreover, the developed emitter’s performance was evaluated in an OLED device. To clarify the influence of the donor number and structural symmetry

• of the DF process. The time-resolved spectroscopic analysis of the emitter (10 wt % 1) in an OLED matrix, 4,4’-bis(N-carbazolyl)-1,1’-biphenyl (CBP), revealed that the emission at 300 K yields a weaker DF when compared to the Zeonex® matrix (Figure 3c). In addition, the emission in CBP was more

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

• Technology (KIT), Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany 10.3762/bjoc.17.197 Abstract In this work we showcase the emitter DICzTRZ in which we employed a twin-emitter design of our previously reported material, ICzTRZ. This new system presented a red-shifted emission at 488

• nm compared to that of ICzTRZ at 475 nm and showed a comparable photoluminescence quantum yield of 57.1% in a 20 wt % CzSi film versus 63.3% for ICzTRZ. The emitter was then incorporated within a solution-processed organic light-emitting diode that showed a maximum external quantum efficiency of 8.4

• light exiting the device. However, when the transition dipoles of the emitter are randomly oriented then only around 20% of the light can escape the device [10]. Indolocarbazole (ICz)-based emitters have been recently employed in several high-performance and highly horizontally oriented materials. ICz

Exploring the possibility of using fluorine-involved non-conjugated electron-withdrawing groups for thermally activated delayed fluorescence emitters by TD-DFT calculation

• Dongyang Chen and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2021, 17, 210–223, doi:10.3762/bjoc.17.21

• donors are present in the emitter design (Type II molecules), now both S1 and T1 states possess CT character. For molecules 2CzOCF3 and 5CzOCF3, the singlet energies are predicted to be 3.92 eV and 3.45 eV; however, the singlet-triplet energy gaps, ΔESTs, are predicted to be large at 0.46 eV and 0.37 eV

• carbazoles was disposed meta or para to the cyano acceptor [19]. OLEDs fabricated using 2,6-2CzBN as the emitter exhibited deep blue emission with λEL = 418 nm and CIE coordinate of (0.15, 0.05); however, due to the low photoluminescence quantum yields (ΦPLs) (28% in 10 wt % DPEPO films) and relatively slow

• ]. Huang et al. also adopted a multiple donor strategy in concert with the weak trifluoromethyl (CF3) acceptor group in their TADF emitter design. The blue-emitting TADF emitter 5CzCF3 possessed a miniscule measured ΔEST of 0.02 eV and ΦPL of 43% in oxygen-free toluene [25]. The solution-processed device

Naphthalonitriles featuring efficient emission in solution and in the solid state

• Sidharth Thulaseedharan Nair Sailaja,
• Iván Maisuls,
• Jutta Kösters,
• Alexander Hepp,
• Andreas Faust,
• Jens Voskuhl and
• Cristian A. Strassert

Beilstein J. Org. Chem. 2020, 16, 2960–2970, doi:10.3762/bjoc.16.246

• . Also, by varying the water fractions, different phenomena can be observed and tuned by judicious choice of the substituents. Upon increasing the water content of THF solutions with NMe2 (i.e., a pure CT emitter), the luminescence exhibits intensity switching and a red-shift upon coupling/decoupling

Synthesis and highly efficient light-induced rearrangements of diphenylmethylene(2-benzo[b]thienyl)fulgides and fulgimides

• Vladimir P. Rybalkin,
• Sofiya Yu. Zmeeva,
• Lidiya L. Popova,
• Valerii V. Tkachev,
• Andrey N. Utenyshev,
• Olga Yu. Karlutova,
• Alexander D. Dubonosov,
• Vladimir A. Bren,
• Sergey M. Aldoshin and
• Vladimir I. Minkin

Beilstein J. Org. Chem. 2020, 16, 1820–1829, doi:10.3762/bjoc.16.149

• preparative method using a Sweko IP65 LED emitter was applied to convert the 3E-isomer into 3Z with a yield of 84%. The interaction of 3E with benzylamine in the presence of ZnCl2 and HMDS leads to the formation of a mixture of fulgimides 4E (41%) and 4Z (18%). Fulgides 3Z and 7E under similar conditions

• was 3.3·1016 photons·s−1 for the spectral line 365 nm. For preparative purposes a Sweko IP65 (SUL-S1-20W-230-4000K-WH) LED emitter was exploited. Acetonitrile of spectroscopic grade (Aldrich) was used to prepare solutions. Melting points were determined on a PTP (M) instrument. X-ray diffraction study

Pauson–Khand reaction of fluorinated compounds

• Jorge Escorihuela,
• Daniel M. Sedgwick,
• Alberto Llobat,
• Mercedes Medio-Simón,
• Pablo Barrio and
• Santos Fustero

Beilstein J. Org. Chem. 2020, 16, 1662–1682, doi:10.3762/bjoc.16.138

• compounds [8][9]. The former takes advantage of the superb properties of the 18F-radioisotope as positron emitter (t1/2 = 109 min, 97% β+ emission), while the latter benefits from the excellent performance of the 19F isotope in NMR (100% natural abundance, high sensitivity, lack of endogenous background

Five-component, one-pot synthesis of an electroactive rotaxane comprising a bisferrocene macrocycle

• Natalie Lagesse,
• Luca Pisciottani,
• Maxime Douarre,
• Pascale Godard,
• Brice Kauffmann,
• Vicente Martí-Centelles and
• Nathan D. McClenaghan

Beilstein J. Org. Chem. 2020, 16, 1564–1571, doi:10.3762/bjoc.16.128

• an FD emitter with an emitter voltage of 10 kV. The sample (1–2 µL) was deposited on a 13 μm emitter wire. Electrospray spectra (ESI) were recorded on a Qexactive (Thermo) mass spectrometer. The instrument was equipped with an ESI source and spectra were recorded in the positive mode. The spray

Heterogeneous photocatalysis in flow chemical reactors

• Christopher G. Thomson,
• Ai-Lan Lee and
• Filipe Vilela

Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125

Synthesis and properties of quinazoline-based versatile exciplex-forming compounds

• Rasa Keruckiene,
• Simona Vekteryte,
• Ervinas Urbonas,
• Matas Guzauskas,
• Eigirdas Skuodis,
• Dmytro Volyniuk and
• Juozas V. Grazulevicius

Beilstein J. Org. Chem. 2020, 16, 1142–1153, doi:10.3762/bjoc.16.101

• properties [8]. A quinazoline-based emitter exhibiting thermally activated delayed fluorescence (TADF) was also reported [6] and green to yellow TADF OLEDs were fabricated with EQEs from 17.6 to 20.5%. The multicolor emission of a quinazoline–carbazole compound was employed in white OLEDs. White

Aryl-substituted acridanes as hosts for TADF-based OLEDs

• Naveen Masimukku,
• Dalius Gudeika,
• Oleksandr Bezvikonnyi,
• Ihor Syvorotka,
• Rasa Keruckiene,
• Dmytro Volyniuk and
• Juozas V. Grazulevicius

Beilstein J. Org. Chem. 2020, 16, 989–1000, doi:10.3762/bjoc.16.88

• nature of substituents of acridan in compounds 4–6 on the hole-transporting properties was detected. OLED fabrication and characterization To test the studied compounds as host compounds in OLEDs, devices based on the well-known TADF emitter 9-[4-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-N3,N3,N6,N6

• -tetraphenyl-9H-carbazole-3,6-diamine (DACT-II) were fabricated and characterized [33]. The DACT-II-based OLEDs are expected to reach an internal quantum efficiency (IQE) of 100%. The low-energy absorption bands at ≈410 nm of the film of the emitter DACT-II and the emission bands of the films of the studied

• compounds overlapped to a greater extent in case of derivatives 3, 4, and 6 than in case of compound 5, that showed an unsuitably red-shifted emission. Taking this observation into account, DACT-II (10 wt %) was used as the emitter doped into hosts 3, 4, and 6 in OLEDs A, B and C, respectively. The

Synthesis and optoelectronic properties of benzoquinone-based donor–acceptor compounds

• Daniel R. Sutherland,
• Nidhi Sharma,
• Georgina M. Rosair,
• Ifor D. W. Samuel,
• Ai-Lan Lee and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2019, 15, 2914–2921, doi:10.3762/bjoc.15.285

• noble metal complex, such as those based on iridium(III) [22]; (2) triplet–triplet annihilation (TTA) [23], or (3) TADF. The maximum IQE for TTA is 62.5%, whereas for TADF, it is as high as 100% [24]. TADF emitter development has thus emerged as an effective avenue to achieve high performance in OLEDs

• of the TADF emitter requires that the highest occupied molecular orbital (HOMO) must be spatially well-separated from the lowest unoccupied molecular orbital (LUMO), such that the exchange integral is minimized [25][26]. Due to a ′trade-off′ between ΔEST and high fluorescence radiative rates [27], it

• use in highly efficient, orange-to-red OLEDs (λEL ranging from 584–637 nm, EQEmax ranging from 6.9–12.5%) [29], to the best of our knowledge, no benzoquinone-based compounds have been investigated in the context of TADF emitter design. The stronger acceptor character of benzoquinone is attractive

A photochemical determination of luminescence efficiency of upconverting nanoparticles

• Baptiste Amouroux,
• Clément Roux,
• Jean-Claude Micheau,
• Fabienne Gauffre and
• Christophe Coudret

Beilstein J. Org. Chem. 2019, 15, 2671–2677, doi:10.3762/bjoc.15.260

• of “optically active” ions: a sensitizer (often ytterbium) and an emitter (“activator”) such as thulium (UV and blue emissions), holmium (red) or erbium (mostly green). In this solid solution, energy collected by ytterbium at 976 nm is transferred to the less abundant emitting ions. Thanks to

Plasma membrane imaging with a fluorescent benzothiadiazole derivative

• Pedro H. P. R. Carvalho,
• Jose R. Correa,
• Karen L. R. Paiva,
• Daniel F. S. Machado,
• Jackson D. Scholten and
• Brenno A. D. Neto

Beilstein J. Org. Chem. 2019, 15, 2644–2654, doi:10.3762/bjoc.15.257

• its selectivity seems to be smaller than the one observed for the new green emitter. Although the plasma membrane separates the interior of the cell from the extracellular environment, there is a massive material transfer between both sides [59]. These materials typically are transported by vesicles

• affinity for the plasma membrane as depicted in the imaging (qualitative and quantitative) experiments. Theoretical calculations were found to be in accordance with the experimental data and helped to understand the ICT stabilizing process of the designed fluorophore. The developed green emitter was

Synthesis, photophysical and electrochemical properties of pyridine, pyrazine and triazine-based (D–π–)₂A fluorescent dyes

• Keiichi Imato,
• Toshiaki Enoki,
• Koji Uenaka and
• Yousuke Ooyama

Beilstein J. Org. Chem. 2019, 15, 1712–1721, doi:10.3762/bjoc.15.167

• also by the electronic characteristics of the π bridge. Consequently, the D–π–A dyes are of considerable practical concern as a useful fluorescence sensor for cation, anion and neural species [5][6][7][8][9][10][11][12][13][14], an efficient emitter for organic light emitting diodes (OLEDs) [15][16][17

Organometallic vs organic photoredox catalysts for photocuring reactions in the visible region

• Aude-Héloise Bonardi,
• Frédéric Dumur,
• Guillaume Noirbent,
• Jacques Lalevée and
• Didier Gigmes

Beilstein J. Org. Chem. 2018, 14, 3025–3046, doi:10.3762/bjoc.14.282

• traditionally carried out in the presence of transition metal complexes. In this field, 4CzIPN (Scheme 4) that was reported in the first work of Adachi et al. as a green emitter for OLEDs [69][83][84] was revisited numerous times in organocatalysis. In 2017, it was notably used for the chemoselective and