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

• reaction [39]. Recently, An and co-workers reported a helical, azepine-containing NG 27 by the introduction of an NH in the seco-HBC framwork (Scheme 3). Single-crystal X-ray diffractometry revealed the mixed P/M enantiomers. Taking advantage of the grafting NH functional group, the optical resolution of

• through oxidative cyclodehydrogenation and imine formation in a 72% yield. It was noted that no other regioisomer was detected for the asymmetrical precursor 30. The pair of enantiomers was confirmed by the racemic structure's single-crystal X-ray diffractometry and separated by chiral HPLC, and no

Synthesis and anticancer activity of bis(2-arylimidazo[1,2-a]pyridin-3-yl) selenides and diselenides: the copper-catalyzed tandem C–H selenation of 2-arylimidazo[1,2-a]pyridine with selenium

• Mio Matsumura,
• Tsutomu Takahashi,
• Hikari Yamauchi,
• Shunsuke Sakuma,
• Yukako Hayashi,
• Tadashi Hyodo,
• Tohru Obata,
• Kentaro Yamaguchi,
• Yasuyuki Fujiwara and
• Shuji Yasuike

Beilstein J. Org. Chem. 2020, 16, 1075–1083, doi:10.3762/bjoc.16.94

• . The structures of the diselenide 2a and the selenide 3a were determined by single crystal X-ray diffractometry and are shown in Figure 2. The compounds 2a and 3a both had selenium atoms attached to the 3-positions of their respective imidazo[1,2-a]pyridine rings. The diselenide 2a had a characteristic

Absolute configurations of talaromycones A and B, α-diversonolic ester, and aspergillusone B from endophytic Talaromyces sp. ECN211

• Ken-ichi Nakashima,
• Junko Tomida,
• Takao Hirai,
• Yoshiaki Kawamura and
• Makoto Inoue

Beilstein J. Org. Chem. 2020, 16, 290–296, doi:10.3762/bjoc.16.28

• in good agreement with those of 1 (Figure 3b), the absolute configuration of 2 was also assigned to be R. Single crystals of α-diversonolic ester (3) were obtained as colorless prisms by vapor diffusion with acetone/n-hexane, and single-crystal X-ray diffractometry determined the structure shown in

• derivatives, α-diversonolic ester (3) and aspergillusone B (4), from the cultures of Talaromyces sp. ECN211. The absolute configurations of 3 and 4 had previously only been assigned tentatively and could now be confirmed by single-crystal X-ray diffractometry and ECD spectroscopy. We also revealed the

• absolute configurations of the new derivatives 1 and 2 using extensive spectroscopic analyses as well as single-crystal X-ray diffractometry. Our crystallization efforts resolved the absolute configuration of α-diversonolic ester (3) and its derivatives, which had not been clarified previously

Oxidative phenylamination of 5-substituted 1-hydroxynaphthalenes to N-phenyl-1,4-naphthoquinone monoimines by air and light “on water”

• Julio Benites,
• Juan Meléndez,
• Cynthia Estela,
• David Ríos,
• Luis Espinoza,
• Iván Brito and
• Jaime A. Valderrama

Beilstein J. Org. Chem. 2014, 10, 2448–2452, doi:10.3762/bjoc.10.255

• and potential of this methodology are under way in our laboratory. Structures of compounds 1–3. Structure of compound 6 determined by single crystal X-ray diffractometry. Hypothetical one-pot synthesis of compound 4a and/or 4b. Evaluation of the substrate scope using RB as oxygen (1O2) sensitizer “on