A facile route to bis(pyridyl-1,3,5-triazine) ligands with fluorescing properties

We present a general method for the preparation of bis(pyridyl-1,3,5-triazine) (dpt) ligands via Stille coupling chemistry. The synthetic procedure surpasses known trimerisation procedures in terms of yield, flexibility, and diversity, as ditopic ligands with different spacers are now available. Polythiophene spacers give rise to different colours by extending the conjugated system and increasing HOMO energy levels. The luminescence properties can be tuned by the spacers, the emission is found in the region from 300-550 nm with nanosecond lifetimes. Preliminary experiments indicate thermochromic properties for the dpt-FeII complexes.