Novel chalcone analogs derived from 4-(benzyloxy)benzaldehyde

Eight chalcone analogs were prepared through an aldol condensation starting from 4-(benzyloxy)benzaldehyde and either less common acetophenones or a few selected heteroaryl methyl ketones. The reaction has been performed through the classical approach that employs an alkali as catalyst for five chalcone analogs, while a variant that uses piperidine as basic catalyst was employed for the other three chalcone analogs. The structure of the resulting enones has been established by NMR spectroscopy. Photoinduced dimerization of a selected benzyloxy-substituted chalcone analog under irradiation with UV light for periods of time ranging from 30 minutes to 24 h has also been monitored using NMR spectroscopy. Analysis of the results demonstrated the presence of the E isomer of the chalcone analog along with three regioisomeric cyclobutanes in the irradiated sample.