title: Proton-driven self-assembled systems based on cyclam-cored dendrimers and [Ru(bpy)(CN)4]2-.
abstract: 1,4,8,11-tetraazacyclotetradecane (cyclam), which is one of the most extensively investigated ligands in coordination chemistry, in its protonated forms, can play the role of host toward cyanide metal complexes. We have investigated the acid-driven adducts formed in acetonitrile-dichloromethane (1:1 v/v) solution by [Ru(bpy)(CN)4](2-) with 1,4,8,11-tetrakis(naphthylmethyl)cyclam (1) and a dendrimer consisting of a cyclam core appended with 12 dimethoxybenzene and 16 naphthyl units (2). [Ru(bpy)(CN)4](2-), 1, and 2 exhibit characteristic absorption and emission bands, in distinct spectral regions, that are strongly affected by addition of acid. When a solution containing equimolar amounts of [Ru(bpy)(CN)4](2-) and 1 or 2 is titrated by trifluoroacetic acid, or when [Ru(bpy)(CN)4](2-) is titrated with (1.2H)2+ or (2.2H)2+, [[Ru(bpy)(CN)4](2-).(2H+).1] or [[Ru(bpy)(CN)4](2-).(2H+).2] adducts are formed in which the fluorescence of the naphthyl units is strongly quenched by very efficient energy transfer to the metal complex, as shown by the sensitized luminescence of the latter. The [[Ru(bpy)(CN)4]2-.(2H+).1] and [[Ru(bpy)(CN)4](2-).(2H+).2] adducts can be disrupted (i) by addition of a base (1,4-diazabicyclo[2.2.2]octane), yielding the starting species [Ru(bpy)(CN)4](2-) and 1 or 2, or (ii) by further addition of triflic acid, with formation of (1.2H)2+ or (2.2H)2+ and protonated forms of [Ru(bpy)(CN)4](2-). It is shown that upon stimulation with two chemical inputs (acid and base) both [[Ru(bpy)(CN)4](2-).(2H+).1] and [[Ru(bpy)(CN)4](2-).(2H+).2] exhibit two distinct optical outputs (a naphthalene-based and a Ru(bpy)-based emission) that behave according to an XOR and an XNOR logic, respectively.
authors.affiliation: Dipartimento di Chimica G. Ciamician, Università di Bologna, via Selmi 2, I-40126 Bologna, Italy.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Bergamini
authors.forename: Christophe
authors.initials: C
authors.lastname: Saudan
authors.forename: Paola
authors.initials: P
authors.lastname: Ceroni
authors.forename: Mauro
authors.initials: M
authors.lastname: Maestri
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Balzani
authors.forename: Marius
authors.initials: M
authors.lastname: Gorka
authors.forename: Sang-Kyu
authors.initials: SK
authors.lastname: Lee
authors.forename: Jeroen
authors.initials: J
authors.lastname: van Heyst
authors.forename: Fritz
authors.initials: F
authors.lastname: Vögtle