10.1021/ja0317067.s001 Claire Fave Claire Fave Muriel Hissler Muriel Hissler Tamás Kárpáti Tamás Kárpáti Joëlle Rault-Berthelot Joëlle Rault-Berthelot Valérie Deborde Valérie Deborde Loic Toupet Loic Toupet László Nyulászi László Nyulászi Régis Réau Régis Réau Connecting π-Chromophores by σ-P−P Bonds:  New Type of Assemblies Exhibiting σ−π-Conjugation American Chemical Society 2004 chemical modifications band gap HOMO Theoretical studies electroactive materials thienyl substituents biphosphole modifications offer P centers interaction nucleophilic σ 3 UV assembly 2004-05-19 00:00:00 Dataset https://acs.figshare.com/articles/dataset/Connecting_Chromophores_by_P_P_Bonds_New_Type_of_Assemblies_Exhibiting__Conjugation/3338815 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 σ<sup>3</sup>-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.