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Herein we describe the synthesis and structural characterization of a [2x2] metallogrid of Zinc(II) and its ditopic bis(hydrazone) ligand, as well as the evaluation of their photo‐physical and electrochemical properties. The synthesis of the bis(hydrazone) involves an aromatic nucleophilic substitution followed by a condensation. Then, through complexation with Zinc(II) ions the [2x2] metallogrid was obtained. The bis(hydrazone) was subjected to UV light‐induced E/Z isomerization determining its kinetic constants through Nuclear Magnetic Resonance (NMR). A clear effect of the metal and the structure was observed on the redox potentials of the metallogrid and its ligand when studied by Cyclic Voltammetry (CV) and Osteryoung Square Wave Voltammetry (OSWV). All compounds were also studied through UV‐Vis and Fluorescence spectroscopy, observing, in some cases, a pronounced pH‐effect. Our results indicate that the photophysical properties of metallogrid can be tuned through the elimination of the acidic protons from the bis(hydrazone) ligands and, together with their electrochemical properties can be used as molecular switches.

Microwave-Assisted Synthesis of Fused Pyrazolo[3,4-b]pyrazines by the Reaction of ortho-Aminonitrosopyrazoles and Cyclicβ-Diketones. -(QUIROGA*, J.; SANCHEZ, N. E.; ACOSTA, P.; INSUASTY, B.; ABONIA, R.; Tetrahedron Lett. 53 (2012) 25, 3181-3187, http://dx.