Fluorescent Photoinduced Electron Transfer (PET) Sensing Molecules with p-Phenylenediamine as Electron Donor
摘要:
Fluorescent photoinduced electron-transfer sensors were made from p-phenylenediamine-substituted azacrown ethers attached with a dansyl group, in which the p-phenylenediamine moiety serves as electron donor and the dansyl group acts as the acceptor. Chelation-enhanced fluorescence was observed upon addition of metal salts. Selective fluorescence response was observed for Mg2+ and/ or Ca2+ versus Na+ and K+ due to size match and charge density sensitivity of the p-phenylenediamine moiety.
The nucleophilic aromatic substitution under ultrasound irradiation of a dichlorobenzene iron η6-complex with various secondary amines is reported. The reaction time at moderate temperatures is considerably shortened (15 min) compared to non sonicated reaction conditions at room temperature (several days) or at solvent refluxing temperature (12–48 h). Controlled mono- or di-substitution was achieved