Synthesis, characterization, and photophysical properties of novel 9‑phenyl-9-phosphafluorene oxide derivatives

• Shuxian Qiu,
• Duan Dong,
• Jiahui Li,
• Huiting Wen,
• Jinpeng Li,
• Yu Yang,
• Shengxian Zhai and
• Xingyuan Gao

Beilstein J. Org. Chem. 2024, 20, 3299–3305, doi:10.3762/bjoc.20.274

• hand, we turned our attention to the synthesis of PhFlOP-based compounds through a Cs2CO3-facilitated nucleophilic substitution with substituted carbazoles as the nucleophiles (Scheme 2). For example, tert-butyl, bromo, carbazolyl, or phenyl substituents were introduced into the carbazoles. To our

• delight, by treatment of 5 with substituted carbazoles 6 in the presence of Cs2CO3 (5.0 equiv) in DMF at 100 °C, seven 2,8-bis(9H-carbazol-9-yl)-5-phenylbenzo[b]phosphindole 5-oxide derivatives 7 were furnished in good to excellent yields (77–91%). The structural characterization of the obtained molecules

Reactivity of hypervalent iodine(III) reagents bearing a benzylamine with sulfenate salts

• Beatriz Dedeiras,
• Catarina S. Caldeira,
• José C. Cunha,
• Clara S. B. Gomes and
• M. Manuel B. Marques

Beilstein J. Org. Chem. 2024, 20, 3281–3289, doi:10.3762/bjoc.20.272

• have been reported [12]. These reagents have proven effective in delivering azides (I) [13], amides (II) [14], aliphatic cyclic amines (III) [15], phthalimidates (IV) [16], imines (V) [17], sulfoximides (VI) [18], carbazoles (VII) [19], secondary (VIII) [4] and primary (IX) [20] amines (Figure 1). The

• benziodoxol(on)es can be found in the literature, including reagents featuring cyclic aliphatic amine moieties (III) [15], phthalimidates (IV) [16], and carbazoles (VII) [19]. Minakata and co-workers proposed an innovative approach for transferring imine groups using iodane-containing (diarylmethylene)amino

Synthesis of 4-functionalized pyrazoles via oxidative thio- or selenocyanation mediated by PhICl₂ and NH₄SCN/KSeCN

• Jialiang Wu,
• Haofeng Shi,
• Xuemin Li,
• Jiaxin He,
• Chen Zhang,
• Fengxia Sun and
• Yunfei Du

Beilstein J. Org. Chem. 2024, 20, 1453–1461, doi:10.3762/bjoc.20.128

• of efforts to developing efficient thio/selenocyanation approaches [33][34][35][36][37][38][39][40][41]. Specifically, a plethora of synthetic strategies have been reported for the thiocyanation of heteroaromatic compounds including arenes, indoles, carbazoles, pyrroles, and imidazopyridines [42][43

Diameter-selective extraction of single-walled carbon nanotubes by interlocking with Cu-tethered square nanobrackets

• Guoqing Cheng and
• Naoki Komatsu

Beilstein J. Org. Chem. 2024, 20, 1298–1307, doi:10.3762/bjoc.20.113

• nitrogen atoms of carbazoles are simplified as methyl groups. As shown in Figure 2a and 2b, while both of them have rectangular structures, the shape of 1b is almost square. As shown in Figure 2b, the distances between the two nitrogen atoms at carbazoles in 1b are 18.35 and 18.07 Å along the pyrene and Cu

• -dipyrrins, respectively. The corresponding distances in 1a are 14.13 and 18.07 Å along the anthracene and Cu-dipyrrins, respectively, as shown in Figure 2a. Meanwhile, the dihedral angles between pyrene and carbazoles in 1b are 34.2°, which is much smaller than those of anthracene (89.7°), due to less

• ], which is consistent with the above calculation result. In the optimized structures of 1a@(9,4)-SWNT and 1b@(12,2)-SWNT complexes (Figure 6b and 6c, respectively), while CH–π interactions of the four carbazoles with the SWNT surface stabilize the former complex, the carbazoles facing to the SWNT surface

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

• ]. In addition to anilino groups, a myriad of donor entities, including urea-substituted phenyl groups [18][19], carbazoles [20], phenothiazines [21][22], thiophenes [23][24][25][26], tetrathiafulvalenes (TTFs) [27], extended TTFs [28], ferrocenes [27][29][30][31][32][33][34][35][36][37][38][39][40][41

Synthesis of N-acyl carbazoles, phenoxazines and acridines from cyclic diaryliodonium salts

• Nils Clamor,
• Mattis Damrath,
• Thomas J. Kuczmera,
• Daniel Duvinage and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2024, 20, 12–16, doi:10.3762/bjoc.20.2

• Bremen, Germany 10.3762/bjoc.20.2 Abstract N-Acyl carbazoles can be efficiently produced through a single-step process using amides and cyclic diaryliodonium triflates. This convenient reaction is facilitated by copper iodide in p-xylene, using the commonly found activating ligand diglyme. We have

• tested this method with a wide range of amides and iodonium triflates, proving its versatility with numerous substrates. Beyond carbazoles, we also produced a variety of other N-heterocycles, such as acridines, phenoxazines, or phenazines, showcasing the robustness of our technique. In a broader sense

• , this new method creates two C–N bonds simultaneously based on a mono-halogenated starting material, thus allowing heterocycle formation with diminished halogen waste. Keywords: carbazoles; heteroaromatics; iodanes; metal-catalyzed; one-pot reaction; Introduction N-Acyl carbazoles are effective

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 47.7 cd A−1, 42.8 lm W−1, and 21.2%, respectively (Figure 1). Since then, this moiety has been modified by many scientific groups to improve its electroactive properties. Various pyridine-3,5-dicarbonitriles bearing substituted carbazoles were synthesized using different donating and accepting

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

• of the Nz moiety originating from its localized distribution of electrons and the high electronegativities of the N and S atoms, whereas its high HOMO level is attributed to the electron-donating property of the attached carbazoles and the π-conjugation of the carbazole–Nz–carbazole fragment. Such

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

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

• naphtho[1,2-d]oxazoles from β-NQS. A) Arylation and vinylation of β-NQS catalyzed by Ni(II) salts. B) Transformation of the 1,2-dicarbonyl group in the fused imidazo[4,5-a] heterocycle. Benzo[a]carbazole and benzo[c]carbazoles fused with 1,2-naphthoquinone. Synthesis of 1,2-naphthoquinones having a C=C

Recent advances in the asymmetric phosphoric acid-catalyzed synthesis of axially chiral compounds

• Alemayehu Gashaw Woldegiorgis and
• Xufeng Lin

Beilstein J. Org. Chem. 2021, 17, 2729–2764, doi:10.3762/bjoc.17.185

• rearomatization-enabled central to axial chirality transfer pathway [73]. Citing the crucial role of di-carbazole-substituted arenes in OLED materials [74], Tan and co-workers have recently developed structural motifs with two chiral N-aryl axes from 2,6-diazonaphthalene 61 and carbazoles 62. For this reaction, a

Visible-light-mediated copper photocatalysis for organic syntheses

• Yajing Zhang,
• Qian Wang,
• Zongsheng Yan,
• Donglai Ma and
• Yuguang Zheng

Beilstein J. Org. Chem. 2021, 17, 2520–2542, doi:10.3762/bjoc.17.169

• transferred electrons to organic halides, thereby achieving the cross-coupling. The detailed mechanistic studies are shown in section 3.2. In 2013, Fu and co-workers [81] reported the photoinduced copper-catalyzed alkylation of carbazoles 41 with alkyl halides 42 and completed the corresponding mechanistic

• ] discovered the asymmetric cross-coupling of racemic tertiary alkyl halides 43 with carbazoles or indoles 44 in the CuI/chiral phosphine system. Under irradiation conditions, excitation of the copper–nucleophile complex A results in the excited state species B that engages in the electron transfer with the

• alkyl halide to generate a copperII–nucleophile complex C and an alkyl radical. The formation of the R–Nu bond might occur through an in-cage pathway involving complex C (Scheme 20). In addition to carbazoles, the authors further described the C–N coupling of organic halides 45 with amides [83] and

Efficient synthesis of polyfunctionalized carbazoles and pyrrolo[3,4-c]carbazoles via domino Diels–Alder reaction

• Ren-Jie Fang,
• Chen Yan,
• Jing Sun,
• Ying Han and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2021, 17, 2425–2432, doi:10.3762/bjoc.17.159

• diastereoisomers of tetrahydropyrrolo[3,4-c]carbazoles, which can be dehydrogenated by DDQ oxidation in acetonitrile at room temperature to give the aromatized pyrrolo[3,4-c]carbazoles in high yields. On the other hand, the one-pot reaction of 3-(indol-3-yl)-1,3-diphenylpropan-1-ones with chalcones or

• benzylideneacetone in acetonitrile in the presence of p-TsOH and DDQ resulted in polyfunctionalized carbazoles in satisfactory yields. The reaction mechanism included the DDQ oxidative dehydrogenation of 3-(indol-3-yl)-1,3-diphenylpropan-1-ones to the corresponding 3-vinylindoles, their acid-catalyzed Diels–Alder

• convenient synthesis of polyfunctionalized carbazole derivatives. Results and Discussion According to our previously established reaction conditions for the preparation of spiro[indoline-3,5'-pyrrolo[3,4-c]carbazoles] [48], an equivalent amount of 3-(indol-3-yl)maleimide with chalcone was stirred in toluene

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

• results showed that when the carbazoles were both located ortho to the cyano acceptor the molecule (2,6-2CzBN) possessed a highly twisted structure and a corresponding small ΔEST (0.27 eV in toluene). The ΔESTs increased to 0.41 (2,4-2CzBN) and 0.40 eV (3,5-2CzBN) in toluene when at least one of the

• 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

• located on the central benzene ring and the acceptor group while the HOMOs are mainly localized on the carbazoles, thereby leading to small ΔESTs. The calculated ΔESTs for 2CzSCF3/2CzSF5 are 0.22 eV and 0.07 eV, respectively, which are comparable to the calculated results for 2CzBN (0.18 eV) and 2CzTRZ

Synthesis, crystal structures and properties of carbazole-based [6]helicenes fused with an azine ring

• Daria I. Tonkoglazova,
• Anna V. Gulevskaya,
• Konstantin A. Chistyakov and
• Olga I. Askalepova

Beilstein J. Org. Chem. 2021, 17, 11–21, doi:10.3762/bjoc.17.2

• -2-carbazolylpyridine 6 in 74% yield (Scheme 3). Electrophilic cyclizations of 3-alkynyl-2-carbazolylazines 2a,b and 6 into azine-fused carbazoles 7a–c were carried out with ICl in dry acetonitrile at room temperature in the dark (Table 3). In the cases of compounds 2a,b, the reaction was found to be

Synthesis and characterization of S,N-heterotetracenes

• Astrid Vogt,
• Florian Henne,
• Christoph Wetzel,
• Elena Mena-Osteritz and
• Peter Bäuerle

Beilstein J. Org. Chem. 2020, 16, 2636–2644, doi:10.3762/bjoc.16.214

• provide carbazoles covering a wide substrate and functional group spectrum [41]. Moreover, penta- and heptafused heteroacenes were prepared by the Cadogan reaction by annulation of nitrophenyl or nitrobenzothienyl precursors [42][43][44][45]. In this respect, we recently reported a Cadogan cyclization of

Recent developments in enantioselective photocatalysis

• Callum Prentice,
• James Morrisson,
• Andrew D. Smith and
• Eli Zysman-Colman

Beilstein J. Org. Chem. 2020, 16, 2363–2441, doi:10.3762/bjoc.16.197

When metal-catalyzed C–H functionalization meets visible-light photocatalysis

• Lucas Guillemard and
• Joanna Wencel-Delord

Beilstein J. Org. Chem. 2020, 16, 1754–1804, doi:10.3762/bjoc.16.147

• . Thus, an efficient method for the synthesis of carbazoles via an intramolecular C–H amination was developed, using N-substituted 2-aminobiaryl derivatives as the substrates (Figure 11) [76]. This procedure was carried out at 80 °C and led to the formation of various interesting coupling products with

• hydrogen, benzyl, or alkyl, resulted in the shut of reactivity and no formation of the corresponding N-substituted carbazoles was observed. Concerning the mechanism, the carbazole-forming reaction also required aerobic conditions in order to reoxidize the Ir-photocatalyst with molecular oxygen (Figure 12

Recent advances in photocatalyzed reactions using well-defined copper(I) complexes

• Mingbing Zhong,
• Xavier Pannecoucke,
• Philippe Jubault and
• Thomas Poisson

Beilstein J. Org. Chem. 2020, 16, 451–481, doi:10.3762/bjoc.16.42

• large panel of carbazoles. The selectivity of the reaction using an unsymmetrical triarylamine depended on the electronic density of the aromatic ring, furnishing, in some cases constitutional isomers. Importantly, in the case of heteroaryl-substituted triarylamines, the heterocycle was incorporated in

Recent developments in photoredox-catalyzed remote ortho and para C–H bond functionalizations

• Rafia Siddiqui and
• Rashid Ali

Beilstein J. Org. Chem. 2020, 16, 248–280, doi:10.3762/bjoc.16.26

• amination of ortho positions: synthesis of carbazoles Although a handful of methods for the construction of carbazoles, which are biologically important, is available in the literature, these procedures suffer from the need for an elevated temperature and the requirement of stoichiometric amounts of strong

• formation of carbazoles from biaryl derivatives. Mechanism for the synthesis of phenol derivatives with photoredox catalyst 8. Possible mechanism for the generation of phenols with the aid of photoredox catalyst 5. Proposed mechanism for the synthesis of monobrominated compounds. Mechanism for the synthesis

• purines via dual photoredox catalysis. Arylation of substituted arenes with an organic photoredox catalyst. C–H trifluoromethylation. Synthesis of benzo-3,4-coumarin derivatives. Oxidant-free oxidative phosphonylation. Nitration of anilines. Synthesis of carbazoles via intramolecular amination. Synthesis

Synthesis of 3-alkenylindoles through regioselective C–H alkenylation of indoles by a ruthenium nanocatalyst

• Abhijit Paul,
• Debnath Chatterjee,
• Srirupa Banerjee and
• Somnath Yadav

Beilstein J. Org. Chem. 2020, 16, 140–148, doi:10.3762/bjoc.16.16

• years, as these are the vital structural motifs of several biologically and medicinally important compounds [1][2][3][4]. Also, 3-alkenylindoles act as fundamental building blocks for the synthesis of materials such as carbazoles [5][6], indole alkaloids [7][8][9], etc. Again, 3-alkenylindoles also form

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

• carbazoles with respect to the bridging benzene of ca. 44° in both 3 and 4 (Figure 2). Theoretical properties Density functional theory (DFT) calculations were performed in the gas phase to assess the electronic structures of 2–5 (see Supporting Information File 1 for details). The S1 and T1 excited states

Regioselective Pd-catalyzed direct C1- and C2-arylations of lilolidine for the access to 5,6-dihydropyrrolo[3,2,1-ij]quinoline derivatives

• Hai-Yun Huang,
• Haoran Li,
• Thierry Roisnel,
• Jean-François Soulé and
• Henri Doucet

Beilstein J. Org. Chem. 2019, 15, 2069–2075, doi:10.3762/bjoc.15.204

• groups. The one pot access to α,β-diarylated lilolidines with two identical aryl groups is also possible by using a larger amount of aryl bromide. The synthesis of 5,6-dihydrodibenzo[a,c]pyrido[3,2,1-jk]carbazoles from lilolidine via three successive direct arylations is also described. Therefore, this

• aryl groups at α- and β-positions via two-fold Pd-catalyzed C–H bond functionalizations, iii) on the synthesis of 5,6-dihydrodibenzo[a,c]pyrido[3,2,1-jk]carbazoles via three successive C–H bond functionalization steps (Scheme 1c). Results and Discussion Based on our previous results on the arylation of

• ) catalyst associated to KOAc provided the desired diarylated lilolidines 23–26 in 55–87% yields. The structure of 23 was confirmed by X-ray diffraction. Finally, the synthesis of 5,6-dihydrodibenzo[a,c]pyrido[3,2,1-jk]carbazoles via β-arylation of the previously obtained α-arylated lilolidines followed by

Oxidative radical ring-opening/cyclization of cyclopropane derivatives

• Yu Liu,
• Qiao-Lin Wang,
• Zan Chen,
• Cong-Shan Zhou,
• Bi-Quan Xiong,
• Pan-Liang Zhang,
• Chang-An Yang and
• Quan Zhou

Beilstein J. Org. Chem. 2019, 15, 256–278, doi:10.3762/bjoc.15.23

• [2,3-c]dihydrocarbazoles 70 and [2,3-c]carbazoles 71 (Scheme 15) [91]. This process permitted the use of readily available and cheap AgOAc as the catalyst and oxidant, and DMF as the solvent. Notably, the product 70 was easily transformed into 71 in the presence of chloranil (1.4 equiv) at 120 °C under

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

• ]. Its absorption extends from UV until 450 nm and can thus be activated at 405 nm with a blue light. Eventually, the peripheral carbazoles can be substituted with halogens. This increases the rate of RISC, and red-shifts the absorption spectrum [81]. For example, with a bromo atom on the peripheral

• hydrocarbons [93], heteropolyacenes [90][91], carbazoles [80][81][94], triazines [95], pentacenes [96], diketopyrrolopyrroles [24] and perylene [97][98] derivatives have been investigated as organocatalysts as exemplified in Scheme 5. 3 Comparison of the efficiency of these photoredox catalysts in