To study the ability of σ-P-P skeleton to mediate interaction between π-chromophores, 1,1′-biphospholes bearing phenyl or thienyl substituents at the 2,2′ and 5,5′-position have been prepared and studied. These air-stable derivatives are readily available via a "one-pot" synthesis starting from diynes. Theoretical studies and UV-vis data clearly establish that the two π-systems interact via the σ-P-P bridge. This through-bond interaction results in a lowering of the optical HOMO-LUMO gap of the assemblies. The nucleophilic σ3-P centers of these 1,1′-biphospholes allow chemical modifications of the σ-bridge. These modifications offer further tuning of the optical properties of the assembly. Electrooxidation of the thienyl-substituted 1,1′-biphosphole results in electroactive materials characterized by low optical band gap and reversible p-doping.
ASJC Scopus subject areas
- Colloid and Surface Chemistry