Water-soluble calix[4]resorcinarenes containing 3- and 4-hydroxyproline, d-nipecotic acid, (S)-2-(methoxymethyl)pyrrolidine, (S)-2-pyrrolidine methanol, and (S,S)-(+)-2,4-bis(methoxymethyl)pyrrolidine substituents are synthesized and evaluated as chiral NMR solvating agents. The derivatives with the hydroxyproline groups are especially effective at causing enantiomeric discrimination in the spectra of water-soluble cationic and anionic compounds with pyridyl, phenyl, and bicyclic aromatic rings. Binding studies show that mono- and ortho-substituted phenyl rings associate within the cavity of the calix[4]resorcinarenes, as do naphthyl rings with mono-, 2,3-, and 1,8-substitution patterns. Anthracene derivatives with an amino or sulfonyl group at the 1-position bind within the cavity, as well. Aromatic resonances of the substrates exhibit substantial upfield shifts because of shielding from the aromatic rings of the calix[4]resorcinarene. The effectiveness of the reagents at producing chiral recognition in 1H NMR spectra is demonstrated with sodium mandelate, the sodium salt of tryptophan, and doxylamine succinate. While no one reagent is consistently the most effective, the calix[4]resorcinarenes with trans-4-hydroxyproline and trans-3-hydroxyproline moieties generally produce the largest nonequivalence in the 1H NMR spectra of the substrates.

9-(N,N-Dianisylamino)anthracene (9DAAA), 9-(N,N-dianisylamino)dinaphth([1,2-a:2'-1'-j]-anthracene (9DAAH), and 9,10-bis(N,N-dianisylamino)anthracene (910BAA) were synthesized as highly twisted triarylamines with potential for photoexcited internal charge transfer. Crystallography of 9DAAA shows its dianisylamino group to be twisted nearly perpendicular to its anthracene unit, similar to a report for 910BAA. The solution fluorescence spectra show strong bathochromic shifts for each of the three molecular systems with strongly decreased quantum efficiency in higher polarity solvents. Solution-phase (ensemble) time-resolved photoluminescence measurements show up to 4-fold decreases in fluorescence lifetime in acetonitrile compared to hexane. The combined results are consistent with photoinduced, transient intramolecular charge-transfer from the bis-anisylamine unit to the polycyclic aromatic unit. Computational modeling is in accord with intramolecular transfer of electron density from the bis-anisylamino unit to the anthracene, based on in comparisons of HOMO and LUMO.

Towards highly luminescent aggregates: A highly twisted triphenylamine displays aggregation-induced enhanced emission. A solvent-specific critical molecular aggregate size, once reached, gives rapid onset of enhanced emission in polar solvent mixtures that favor quenching of solvated individual molecule excited states.

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2-Bromo-1,3-bis[2-(2-naphthyl)vinyl]benzene benzene hemisolvate, C(30)H(21)Br·0.5C(6)H(6), (I), with two formula units in the asymmetric unit, exists in the crystal structure in a conformation in which the trans (2-naphthyl)vinyl substituents on the central bromobenzene moiety appear as nearly fully extended `wings', while 9-bromodinaphth[1,2-a:2',1'-j]anthracene, C(30)H(17)Br, (II), adopts a highly nonplanar `manta-ray' shape, with the H atoms in the interior of the molecule within van der Waals contact distances. The packing of the significantly twisted molecules of (I) generates large voids which are filled by benzene solvent molecules, while molecules of (II) stack compactly with all C-Br bonds parallel within the stack.