Here we report on a novel system based on aromatic thioethers with unique luminescence properties. Fifteen different compounds were investigated in detail on their luminescence properties using UV/Vis absorption and steady-state and time-resolved luminescence spectroscopy. Excited state lifetimes as well as quantum yields were determined, and the toxicity towards HeLa cells was investigated. Besides X-ray analyses also quantum chemical calculations were performed to gain deeper insights in the unique behavior of this facile system. The studied compounds reveal remarkable fluorescence emission ranging from 437 to 588 nm as well as phosphorescence (up to 5 μs).

Five peri-substituted naphthalene and acenaphthalene complexes (Ph 2 Pn) 2 Naph (E = Sb 1, Bi 3), (Ph 2 Sb) 2 Acenaph (2), (Ph 2 Bi)(Me 3 Sn)Naph (4) and (PhBiNaph) 2 (5) were synthesized and characterized in solution ( 1 H, 13 C NMR, IR) and in the solidstate (sc-XRD). 1-5 show different types of noncovalent intermolecular interactions in the solid-state including NaphÀ H•••π, π•••π and Bi•••π (5) contacts, which were exemplarily (5) quantified by use of density functional theory and local coupled cluster electronic structure theory calculations, demonstrating that the Bi•••π contact provides the main stabilizing contribution. Symmetry-adapted intermolecular perturbation theory calculations showed that this and other contacts are dominated by London dispersion interactions.

In this communication we report the synthesis and characterisation of a novel dianionic compound with aggregation‐induced emission properties. This compound was able to recognize spermine via a multivalent electrostatic interaction leading to a restriction of intramolecular rotation enhancing the fluorescence emission. This recognition was investigated in detail using UV‐Vis and fluorescence spectroscopy. Furthermore the binding stoichiometry was determined via isothermal titration calorimetry. Besides that the structure of the compound was confirmed by X‐ray crystallography. To proof the bivalent binding a singly negatively charged control compound was synthesized showing no specific interaction with the amines screened. Theoretical calculations were performed to get a deeper insight in the molecular structure and the electronic transitions.

In this account, we describe the synthesis of a series of BINOL-based bis- and trisphosphoric acids 11d/e/f, which commonly feature an unusual phosphoric acid monoester motif. This motif is generated by an acid-catalyzed 5-endo-dig cyclization of the 3-alkynyl-substituted BINOL precursors to give the corresponding Furan-annelated derivatives, followed by phosphorylation of the remaining phenolic alcohols. In the cyclization reaction, we observed an unexpected partial racemization in the bis- and tris-BINOL scaffolds, leading to mixtures of diastereomers that were separated and characterized spectroscopically and by X‑ray crystal structure analyses. The cyclization and racemization processes were investigated both experimentally and by DFT-calculations, showing that although the cyclization proceeds faster, the barrier for the acid-catalyzed binaphthyl-racemization is only slightly higher.

The reasons for the unusually small BiÀ TeÀ Bi bond angle of 86.6°observed in the crystal strucure of (Et 2 Bi) 2 Te are investigated by quantum chemical calculations. With the help of coupled cluster theory at the CCSD(T) level it is demonstrated that the structure of an isolated monomer should have a bond angle larger than 90°, despite a BiÀ Bi distance in good agreement with the value of 4.09 Å found in the crystal structure. The discrepancy is resolved by a lengthening of the BiÀ Te bond in the crystal, which is shown to be caused by partial electron transfer from neighbouring molecules to the BiÀ Te σ* orbital. Through symmetry-adapted perturbation theory at the DFT-SAPT level it is shown that London dispersion interactions are highly important for the packing of molecules in the solid state and, in turn, for the small BiÀ TeÀ Bi bond angle.