[2.2](2,7)-Fluorenophanediene, [2.2.2](2,7)-fluorenophanetriene, and their fluorenide ions

New [2,2]Fluorenophanes Give Insights into Asymmetric Charge Transfer-Mediated Exciton Delocalization along the π-π Packing Direction

A series of new [2,2]fluorenophanes has been synthesized and characterized; among them, molecules of crystallographically asymmetric anti-[2.2](1,4)(4,1)fluorenophane (K2C-2) aggregate to form one-dimensional supramolecular chain structures through effective intermolecular π-π overlapping. This, in combination with the synergistic intramolecular π-π interaction, leads to prominent dual emission mediated by charge transfer (CT) exciton delocalization. Support of this new insight is given by mapping the transition density along the π-π packing direction where the intramolecular excitation and intermolecular CT coexist in K2C-2.

A route to a cyclobutane-linked double-looped system via a helical macrocycle

The macrocyclic confinements prefers a solid-state prearrangement of two CC linkers that after photocyclisation quantitatively form a cyclobutane linked double-looped structure with perpendicular orientation of macrocyclic arms.

Synthesis and ring opening reaction of octaoctyl substituted [2.2.2.2](2,7)-fluorenophanetetraene by photooxidation

Octaoctyl substituted fluorenophanetetraene has been synthesized and the photooxidation of the fluorenophanetetraene gives all trans linear fluorenevinylene with aldehyde end groups.

Synthesis of macrocyclic receptors with intrinsic fluorescence featuring quinizarin moieties

An unprecedented class of macrocycles with intrinsic fluorescence consisting of phenolic trimers and quinizarin is developed. Though they are lacking strong hydrogen bonds as observed in calixarenes, the two examples introduced here each adopt a vase-like conformation with all four aromatic units pointing in one direction (syn orientation). This "cone" conformation has been confirmed by NMR spectroscopy, molecular modeling, and X-ray crystallography. The laminar, electron-rich fluorophore as part of the macrocycle allows additional contacts to enclosed guest molecules.