title: Tuning supramolecular aurophilic structures: the effect of counterion, positive charge and solvent.
abstract: The synthesis of the cationic gold(i) complexes [Au(C[triple bond, length as m-dash]CC5H4N)(CH3-PTA)]X (X = I, 1; X = OTf, 4), [Au(C[triple bond, length as m-dash]CC5H4N-CH3)(PTA)]X (X = I, 2; X = OTf = 5; PTA = 1,3,5-triaza-7-phosphatricyclo[3.3.1.13.7]decane) and [Au(C[triple bond, length as m-dash]CC5H4N-CH3)(DAPTA)]X (X = I, 3; X = OTf = 6, DAPTA = 3,7-diacetyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane) results in cationic complexes with unexpected supramolecular assemblies in water ranging from rod-like structures (1) to vesicles (2 and 3) and square-like structures (5 and 6). These morphologies are completely different from the fibers previously obtained with their parent neutral complexes [Au(C[triple bond, length as m-dash]C5H4N)(PTA)] and [Au(C[triple bond, length as m-dash]C5H4N)(DAPTA)]. Nevertheless, the introduction of triflate as a counterion in 1 (complex 4) gives rise to the formation of a highly soluble complex in water which does not display any significant aggregation in solution. These results reveal the importance of the introduction of a positive charge on global supramolecular assemblies and how the counterion can also modify the resulting package. Interestingly, we have also proved that the aggregation of complexes 2, 3, 5 and 6 is also affected by the solvent with direct influence on their absorption and emission properties and the global morphology of the aggregates.
authors.affiliation: Departament de Química Inorgànica i Orgànica, Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona, Spain. laura.rodriguez@qi.ub.es.
authors.forename: Elisabet
authors.initials: E
authors.lastname: Aguiló
authors.forename: Raquel
authors.initials: R
authors.lastname: Gavara
authors.forename: Clara
authors.initials: C
authors.lastname: Baucells
authors.forename: Marta
authors.initials: M
authors.lastname: Guitart
authors.forename: João Carlos
authors.initials: JC
authors.lastname: Lima
authors.forename: Jordi
authors.initials: J
authors.lastname: Llorca
authors.forename: Laura
authors.initials: L
authors.lastname: Rodríguez