Preparation and spectroscopic properties of some new diaroylmethanatoboron difluoride derivatives

Five diaroylmethanatoboron difluoride derivatives were prepared from aryl methyl ketones via Claisen condensation with aromatic esters and followed by complexation with boron trifluoride etherate. Their structures and spectroscopic properties were studied by elemental analysis, IR, NMR, ESI–MS, UV and fluorescence spectroscopy. The results showed that these boron complexes had strong fluorescent peaks in the 400–500 nm range in chloroform and high quantum yields. The emission peaks for boron complexes containing naphthyl group exhibited considerable red shift as compared to those of containing phenyl group.