The preparation and spectroscopic characterization of some symmetrical small molecules
containing the disubstituted (E)-3,3′-bifuranylidene-2,2′-dione chromophore (the so-called Pechmann lactone) and
featuring an extended conjugation are reported. The synthetic approach of such compounds
is based on the Stille–Migita coupling reaction, which is carried out in very mild
conditions, suitable to be applied with the very sensitive Pechmann core. The absorption
and emission spectra of the new molecules obtained have been recorded in solution
and clearly show how their photophysical properties can be modulated by a proper choice
of the (hetero)aromatic terminal groups. The compounds prepared in this study (or
close analogues thereof) have interesting optical properties and could find application
as semiconductors in organic electronics or as near-IR fluorescent dyes.
Key words
Pechmann derivatives - organic dyes - Stille reaction - UV/Vis spectroscopy - optoelectronics
