Nitrogen Heterocyclic Carbon-Rich Materials: Synthesis and Spectroscopic Properties of Dehydropyridoannulene Macrocycles
摘要:
A new series of nitrogen heterocyclic dehydroannulenes 1-3 have been synthesized and their macrocyclic structures assigned using spectroscopic methods. The chiral and planar ground state conformations of 1 and 3, respectively, were determined by semiempirical theoretical calculations. All dehydropyridoannulenes and precursors possessing four aromatic rings functioned as fluorescent chromophores. A detailed spectroscopic investigation into the cation-binding properties of 3 in dilute solution revealed a particularly selective photoluminescence quenching sensory response for Pd-II ions. Cycle 3, as well as 1 and 2, also exhibited reversible proton-triggered luminescence quenching behavior. At higher concentrations, 3 afforded a coordination polymer precipitate with Ag-I ions. Cycles I and 2 and precursors 15, 23, and 29 also undergo thermochemical reactions that may potentially lead to carbon-rich polymers. The physicochemical properties of 1-3 suggest that dehydropyridoarmulenes may serve as a particularly versatile new class of ligands for the creation of novel heteroatom-containing carbon-rich materials with many potential applications in supramolecular materials science and nanotechnology.
Cyclic Donor−Acceptor Circuits: Synthesis and Fluorescence Ion Sensory Properties of a Mixed-Heterocyclic Dehydroannulene-Type Cyclophane
作者:Paul N. W. Baxter
DOI:10.1021/jo0302410
日期:2004.3.1
thiophene (electron donor) and pyridine (electron acceptor) heterocyclic units has been prepared. Macrocycle 5 was characterized by FAB MS and 1H and 13C NMR spectroscopy. Cycle 5 was found to function as a selective precipitation and fluorescence sensor for specific metal ions such as AgI and also exhibited reversible proton-triggered fluorescence quenching behavior. The unique donor−acceptor architecture
新dehydroannulene型环芳5包括噻吩(电子供体)的共轭螺旋框架和吡啶(电子受体)杂环单元已被制备。大环5通过FAB MS以及1 H和13 C NMR光谱法表征。发现周期5充当特定金属离子(例如Ag I)的选择性沉淀和荧光传感器,并且还表现出可逆的质子触发的荧光猝灭行为。独特的供体-受体结构和光谱性质5 这表明它代表了分子传感平台的新型领导者,在21世纪材料科学中具有许多潜在的未来应用。