RESUMEN
Two synthetic nanographenes (NGs), N-H7H and C-H7H, were prepared. N-H7H is doped with nitrogen, and C-H7H is the all-carbon analogue. Both are hexapole [7]helicenes (H7Hs), and their structures were identified by single-crystal X-ray diffraction. Sharp contrasts in absorption (abs λmax , 683 vs. 593â nm), emission (em λmax , 894 vs. 777â nm), and electrochemical behavior (ox E1 , 0.28 vs. 0.53â V) were observed between N-H7H and C-H7H, and the origin of these differences was rationalized by theoretical calculations. Studies on N-H7H and C-H7H set a clear example to elucidate the remarkable effects of N-doping on the physical properties of NGs.
RESUMEN
We report the synthesis and characterization of two hexapole [7]helicenes (H7Hs). Single crystal X-ray diffraction unambiguously confirms the molecular structure. H7H absorbs light, with distinct Cotton effect, from ultraviolet to the near-infrared (λmax = 618 nm). Cyclic voltammetry reveals nine reversible redox states, consecutively from -2 to +6. These chiroptical and electronic properties of H7H are inaccessible from helicene's small homologues.
RESUMEN
We present a series of tripodal ligands L1-3, which fold into hemicages C1-3 by using coordination-driven dynamic combinational chemistry. The identities of these hemicages were characterized using 1H NMR, 1H-1H COSY, DOSY, and ESI-TWIM-MS. Free rotation of the ferrocene structural units in the ligands affords an adaptable directionality, which is essential for the construction of these hemicages. Encapsulation of adamantane by C2 indicates the presence of a well-defined inner cavity as the binding pocket.