title: Cyclophanes containing bowl-shaped aromatic chromophores: three isomers of anti-[2.2](1,4)subphthalocyaninophane.
abstract: The connection of bowl-shaped aromatic boron subphthalocyanines with anti-[2.2]paracyclophane resulted in the first observation of electronic communication between convex and concave surfaces. Three isomers of anti-[2.2](1,4)subphthalocyaninophane, described as concave-concave (CC), convex-concave (CV), and convex-convex (VV) according to the orientation of the subphthalocyanine units, were synthesized and characterized by various spectroscopic techniques, including (1) H NMR, electronic absorption, fluorescence, and magnetic circular dichroism spectroscopy and X-ray crystallography, together with molecular-orbital calculations. On going from the CC system to CV and further to VV, the Q band broadened and finally split as a result of through-space expansion of the conjugated systems, which were also reproduced theoretically.
authors.affiliation: Department of Chemistry, Graduate School of Science, Tohoku University, Sendai 980-8578 (Japan).
authors.forename: Quan
authors.initials: Q
authors.lastname: Liu
authors.forename: Soji
authors.initials: S
authors.lastname: Shimizu
authors.forename: Nagao
authors.initials: N
authors.lastname: Kobayashi
keywords: cyclophanes; ring-current effects; subphthalocyanines; transannular interactions; π conjugation