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A new polymorph of fluorescein hydrazone was fully characterized via single X-ray crystallography. In addition, multiple logic circuits and a Half-Adder operator were designed using the fluorescence and UV-Vis switching responses of the fluorescein compound to different metal cations and pH changes.

A novel and highly soluble bis(hydrazone) was synthesized and characterized by different spectroscopic means. This compound was used as a ditopic ligand for the self-assembly of a grid-like complex using Zn 2+ as metal cation. The structure of this compound was fully confirmed by NMR (1D and 2D). The electronic and electrochemical properties were studied using cyclic voltammetry, Osteryoung square wave voltammetry, and UV-Vis spectroscopy. The present work highlights the use of NMR spectroscopy as a tool to describe and analyse the formation of grid-like complexes based on the rotation of the phenyl group attached to the pyrimidine ring. Furthermore, the electrochemical results showed that the bis(hydrazone) 3 exhibits several different redox processes that are affected by the interaction with the metal cation as observed for the grid-like complex. Although the electrochemical processes are all irreversible, this article aims to be an initial study in the search for supramolecular complexes that can be used as electrochemical switches. Propiedades electrónicas y electroquímicas de una estructura del tipo de Zn(II) ResumenUna nueva bis(hidrazona), altamente soluble en solventes orgánicos comunes, se sintetizó y caracterizó mediante diversas técnicas espectroscópicas. El compuesto se utilizó como ligando ditópico en la construcción de estructuras supramoleculares de tipo rejilla (rejillas supramoleculares o complejos metálicos de tipo rejilla) utilizando Zn 2+ como catión metálico. El complejo supramolecular se confirmó mediante resonancia magnética nuclear RMN-1 H y bidimensional. El arreglo de tipo rejilla se determinó mediante las señales de RMN-1 H del anillo fenilo del ligando orgánico que cambia su velocidad de rotación y, por ende, su ambiente químico al coordinarse en dicho arreglo. Por último, se realizaron estudios de UV-Vis y voltamperometría cíclica y de onda cuadrada, con el fin de determinar las propiedades optoelectrónicas y electroquímicas de estos compuestos. Tanto la bis(hidrazona) como el complejo de tipo rejilla aquí presentados, exhiben varios potenciales de oxidación-reducción, los cuales se estudiaron en detalle mediante las técnicas mencionadas y cuyo estudio sirve de base para el desarrollo futuro de estructuras supramoleculares que puedan utilizarse como interruptores moleculares electroquímicos.

We report a new methodology for the synthesis of two highly symmetric equatorial malonate hexaadducts of C60 fullerene. The synthetic methodology is based on a series of protection and deprotection steps that allow the preparation of a fullerene [60] functionalized with six symmetrical positioned malonate addends without using complicated and expensive separation techniques (highperformance liquid chromatography, HPLC) or long reaction times. This methodology allowed us to prepare the carboxylic adducts 6 (equatorial octacarboxylic tetraadduct of C60) and 8 (equatorial dodecacarboxylic hexakisadduct of C60). As far as we  now, compound 6 has not yet been reported. We also studied the electronic properties of the main compounds by UV-Vis spectroscopy and cyclic voltammetry (CV). The reported fullerene adducts exhibited several reversible reduction processes whose electron transfers are controlled by diffusion.

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