Synthesis and exploratory photophysical investigation of donor‐bridge‐acceptor systems derived from N‐substituted 4‐piperidones

We report a two‐step synthesis for N‐aryl‐ and N‐alkyl‐substituted 4‐piperidones, in which the N substituent can easily be varied. A number of intramolecular donor‐acceptor systems was synthesized from these piperidones by conversion of the carbonyl functionality. The influence of the N‐aryl donor on the electronic absorption and fluorescence spectra was investigated systematically. It was concluded that some systems can be used as efficient fluorescent probes with a high sensitivity for solvent polarity.