Functional phosphorus-based π-conjugated systems: Structural diversity without multistep synthesis
The synthesis and properties of linear π-conjugated systems incorporating phosphole rings are described. Their supramolecular organization in the solid state can be controlled either by chemical modifications or coordination to transition metals of the phosphorus atom. Furthermore, chemical transformations of the phosphole ring allow organizing these P-chromophores in 3D assemblies exhibiting σ-π conjugation or in organometallic ferrocene-like derivatives. Phosphole-pyridine-containing π-conjugated chromophores act as P,N-chelates toward transition-metal ions, giving rise to mono- and di-nuclear complexes. The specific properties of these complexes make them valuable materials for organic light-emitting diodes (OLEDs) and interesting building blocks for the tailoring of π-conjugated systems.