Structure and Photophysical Properties of 2,6-Di-tert-Butyl-4-arylpyrylium 2-Naphthalenesulfonate Ion Pairs in Solution and in the Solid State
摘要:
2,6-Di-tert-butyl-4-arylpyrylium 2-naphthalenesulfonate salts form ion pairs in dimethylcarbonate solution that exhibit charge-transfer absorptions and result in the rapid quenching of the pyrylium fluorescence. Molecular mechanics calculations predict that these ion pairs exist in a T-shaped orientation, but X-ray structural analysis reveals a pi face-to-face arrangement in the solid state. Nuclear Overhauser effect and time-resolved spectroscopic experiments carried out in solution are consistent with a T-shape for the ion pair, but these experiments do not prove that this structural hypothesis is correct.
A facile approach to highly functional trisubstituted furans via intramolecular Wittig reactions
作者:Ko-Wei Chen、Siang-en Syu、Yeong-Jiunn Jang、Wenwei Lin
DOI:10.1039/c0ob00912a
日期:——
An efficient and mild synthesis of trisubstituted furans, starting from α,β-unsaturated ketones, tributylphosphine, and acyl chlorides, is described. The strategy employs the intramolecular Wittig protocol as a key step to install the crucial furan ring, leading to a wide variety of highly functional furans in one step.