Synthesis, structure and π-expansion of tris(4,5-dehydro-2,3:6,7-dibenzotropone)

• Yongming Xiong,
• Xue Lin Ma,
• Shilong Su and
• Qian Miao

Beilstein J. Org. Chem. 2025, 21, 1–7, doi:10.3762/bjoc.21.1

• , expanding its π-skeleton through the Barton–Kellogg and Scholl reactions led to the successful synthesis of a curved polycyclic arene containing three heptagons and two pentagons. Keywords: carbon schwarzites; polycyclic arenes; Scholl reaction; seven-membered carbocycle; Yamamoto coupling; Introduction

• synthesis of 1 using a Ni-mediated Yamamoto coupling reaction and the simultaneous crystallization of its two different conformers from the same solution. Expanding the π-skeleton of 1 through a Barton–Kellogg reaction followed by a subsequent Scholl reaction resulted in a new polycyclic arene (3 in Figure

• trione 1 in hands, we explored the Scholl reaction and thionation reaction of it (Scheme 1b) because these reactions can potentially allow π-expansion of 1. A variety of Scholl reaction conditions, such as AlCl3/NaCl, AlCl3/CuCl2, FeCl3, and DDQ/TfOH, were tested. However, these reactions either left the

Efficient synthesis of fluorinated triphenylenes with enhanced arene–perfluoroarene interactions in columnar mesophases

• Yang Chen,
• Jiao He,
• Hang Lin,
• Hai-Feng Wang,
• Ping Hu,
• Bi-Qin Wang,
• Ke-Qing Zhao and
• Bertrand Donnio

Beilstein J. Org. Chem. 2024, 20, 3263–3273, doi:10.3762/bjoc.20.270

• prepared in high yield via FeCl3-oxidative coupling of 1,2-dialkoxy-4-bromobenzene (Scholl reaction). The new triphenylene derivatives, F3–F12, were prepared in moderate to high yields (51–73%). In addition, three bitriphenylene derivatives were synthesized in a subsequent annulation step from Fn

• ) was synthesized via consecutive Suzuki coupling and Scholl reaction in a total yield of 77%. The synthesis, molecular structures, nomenclature, and synthetic yields of all compounds are shown in general Scheme 1. All prepared molecules were fully characterized by NMR (1H, 19F and 13C), HRMS, and CHN

• '-tetraalkoxy-1,1'-biphenyl (2Br-BPn → 2Li-BPn) e.g., 4F-TPn [44], p-TPFn [46], m-TPFn [46], PHn [45], and Fn (this work); BTPn was synthesized by a Suzuki–Scholl reaction sequence (Scheme S3, Supporting Information File 1). Single crystal structure of 1,2,4-trifluoro-3-(perfluorophenyl)triphenylene (F) viewed

Surprising acidity for the methylene of 1,3-indenocorannulenes?

• Shi Liu,
• Märt Lõkov,
• Sofja Tshepelevitsh,
• Ivo Leito,
• Kim K. Baldridge and
• Jay S. Siegel

Beilstein J. Org. Chem. 2024, 20, 3144–3150, doi:10.3762/bjoc.20.260

• derivative were also recently prepared by a mechanochemical Scholl reaction [23][24][25]. Furthermore, the anion of TBF is stable enough to be easily handled and the crystal structures of a number of common ammonium salts of TBF anion, grown from water, have been reported [26]. Neutral highly acidic

Synthesis of π-conjugated polycyclic compounds by late-stage extrusion of chalcogen fragments

• Aissam Okba,
• Pablo Simón Marqués,
• Kyohei Matsuo,
• Naoki Aratani,
• Hiroko Yamada,
• Gwénaël Rapenne and
• Claire Kammerer

Beilstein J. Org. Chem. 2024, 20, 287–305, doi:10.3762/bjoc.20.30

• precursors of S- and Se-inserted HBCs. The subsequent Scholl reaction allowed the formation of four new C–C bonds, but failed to afford the fully cyclized chalcogen-embedded HBC whatever the conditions tested, presumably due to large strain in line with the size of S and Se atoms as compared with O. The

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

• chiral nanographenes. Keywords: chiral nanographene; helicene; racemization barrier; Scholl reaction; single-crystal X-ray diffractometry; Introduction Graphene, an allotrope of carbon, has captured widespread attention since it was first experimentally demonstrated as a monolayer of carbon atoms [1

• % yield. The Scholl reaction of compound 3 in the presence of FeCl3 and nitromethane led to the [5]helicene containing, seco-HBC-based chiral NG 4 in an 80% yield [33]. Miao and co-workers reported a twisted chiral NG 7 by a partially cyclized Scholl reaction. By treating compound 6 in 2,3-dichloro-5,6

• Scholl reaction conditions (DDQ, H+; or FeCl3, CH3NO2), the aza-[5]helicenes 22 and 24 were obtained respectively with 60% and 23% yields [38]. It was noted that with the installation of two adjacent pyrimidines in this hexarylbenzene precursor, a fully cyclized planar NG was formed toward Scholl

Direct borylation of terrylene and quaterrylene

• Haruka Kano,
• Keiji Uehara,
• Kyohei Matsuo,
• Hironobu Hayashi,
• Hiroko Yamada and
• Naoki Aratani

Beilstein J. Org. Chem. 2020, 16, 621–627, doi:10.3762/bjoc.16.58

• with AlCl3 reproducibly provided a pure terrylene [8]. Scholl reaction using a superacid catalyst in combination with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as oxidant provides a scalable preparation of quaterrylene [9], but unfortunately the low solubility prevents 1H NMR characterization

Synthesis of triphenylene-fused phosphole oxides via C–H functionalizations

• Md. Shafiqur Rahman and
• Naohiko Yoshikai

Beilstein J. Org. Chem. 2020, 16, 524–529, doi:10.3762/bjoc.16.48

• via 1,4-cobalt migration. The resulting 7-hydroxybenzo[b]phosphole derivative was used for further π-extension through Suzuki–Miyaura couplings and a Scholl reaction, the latter closing the triphenylene ring. The absorption and emission spectra of the thus-synthesized compounds illustrated their

• furnished the phosphole-fused ortho-teraryl products 7a–c in moderate to high yields. With the phosphole-fused ortho-teraryl compounds 7 in hand, we next examined their cyclization into triphenylene derivatives by the Scholl reaction (Scheme 3) [30]. The reaction of 7a (0.1 mmol) in the presence of [bis

• (trifluoroacetoxy)iodo]benzene] (PIFA) and BF3·OEt2 in dichloromethane at −78 °C afforded, after 12 h, the desired cyclized product 8a in 59% yield. The reaction could be performed on a 0.5 mmol scale in a similar yield of 58%. Note that other typical reagents used for the Scholl reaction, such as DDQ/CF3CO2H

Six-fold C–H borylation of hexa-peri-hexabenzocoronene

• Mai Nagase,
• Kenta Kato,
• Akiko Yagi,
• Yasutomo Segawa and
• Kenichiro Itami

Beilstein J. Org. Chem. 2020, 16, 391–397, doi:10.3762/bjoc.16.37

• functionalizing poorly soluble compounds, functionalized HBC is typically synthesized by dehydrogenative cyclization, which is called Scholl reaction, of precursors having solubilizing substituents [12][13]. However, the Scholl reaction sometimes causes unexpected rearrangement such as 1,2-aryl shift, and

• , diethyl ether, ethanol, CH2Cl2 and CHCl3. To compare the efficiency of the current method, the stepwise synthesis of 1 was also examined. The synthesis of hexaiodoinated HBC 3 was conducted through Scholl reaction according to a literature procedure [19]. The subsequent Miyaura–Ishiyama borylation [22

• mg, 27%). 1H NMR (600 MHz, CDCl3) δ 9.78 (s, 1H), 1.61 (s, 6H). Stepwise synthesis of 1 from 3 The Scholl reaction of 2 was performed according to a literature procedure [19]. To a 1 L two-necked round bottom flask containing a magnetic stirring bar were added dichloromethane (400 mL) and compound 2