Supramolecular assemblies and photophysical properties of ionic homo- and heteronuclear metallophilic complexes

Abstract

The synthesis of two dinuclear ionic complexes with chemical formula [Au(PR3)2][Au(C≡CC5H4N)2] that contain the water soluble phosphines, PR3, PTA (1, 3,5-triaza-7-phosphaadamantane, 1) and DAPTA (3,7-diacetyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane, 2) is herein described. The differences on their intermolecular reorganization have been analyzed and compared with the previously reported for the neutral complexes [Au(PR3)(C≡CC5H4N)]. It has been evidenced that the reorganization of the ligands giving rise to the dinuclear ionic complexes produces a complete change in the properties giving rise to Au***Au intermolecular assemblies. These aurophilic contacts are the responsible for the resulting luminescence which is not displayed for the parent compounds [Au(PR3)2]Cl and [PPh4][Au(C≡CC5H4N)2]. Compounds 1 and 2 were made react with three different silver salts (nitrate, triflate and hexafluorophosphate) giving rise to 1:1 heterometallic assemblies with some changes both on the wavelength and emission intensity.