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Formation of coordination networks is a complex process affected by a multitude of factors. Many synthetic strategies have been developed that attempt to control these factors and direct the structure of the final product. Coordination bond formation and structural assembly processes, however, typically take place either in the solution or solid states. In comparison, gas‐phase network synthesis remains largely unexplored. Herein, two new two‐dimensional coordination networks are obtained from the solid–gas phase reaction between ZnX2 (X=I, Br) and the redox‐active 2,5,8‐tri(4‐pyridyl)1,3‐diazaphenalene (HTPDAP) ligand. Their structures were solved by ab initio powder X‐ray diffraction analysis and feature a novel Zn halide trimeric cluster. This strategy is contrasted with a conventional solvothermal synthesis, which led to a one‐dimensional coordination polymer instead. The intrinsic electroactive properties of these materials were probed by solid‐state cyclic voltammetry measurements, which revealed the presence of HTPDAP and halide‐based processes. Chemical oxidation of the two‐dimensional networks by using NOPF6 agent, unexpectedly, led to the formation of a nitrated analog of HTPDAP, the PF6− salt of diprotonated 4,6,7,9‐tetranitro‐2,5,8‐tris(4‐pyridyl)diazaphenalene cation (denoted N‐TPDAP), which was isolated and characterized. These results provide deeper insights into the oxidation process of HTPDAP‐containing networks and uncover unique redox‐induced chemical transformations. [ABSTRACT FROM AUTHOR]

A cyclic (amino)metal‐substituted dicoordinated silylene derivative has been synthesized and fully characterized. Of particular interest is that the N‐hetero‐RhI‐metallacyclic silylene exhibits a distorted tetrahedral geometry around the rhodium atom and a considerably shortened Si−Rh bond (2.138 Å) compared to classical Si−Rh single bonds (ca. 2.30–2.35 Å). A theoretical investigation reveals that the geometrical deviation around the rhodium center from the classical square‐planar to a tetrahedral geometry increases the π‐donating and σ‐accepting character of the rhodium atom, thereby efficiently stabilizing the silylene moiety. [ABSTRACT FROM AUTHOR]

An isolable donor-stabilized silavinylidene phosphorane was synthesized. This molecule, which can also be regarded as a new carbon(0) complex featuring a phosphine and a donor-stabilized silylene ligand, presents a central carbon atom with a remarkably high electron density (−1.82). Furthermore, the experimental electron-density study of this compound demonstrates the delocalization of the σ-lone pair at the central carbon atom toward the silicon center, a feature which is remarkably different from electronic situation of other bent-allene-type molecules. This result clearly demonstrates the powerful electron-donating ability of donor-stabilized silylene ligands, as well as their excellent electron-acceptor properties. [ABSTRACT FROM AUTHOR]

A donor-stabilized 1,3-disila-2,4-diazacyclobutadiene presents an exceptionally short nonbonded Si⋅⋅⋅Si distance (2.23 Å), which is as short as that of Si=Si bonds (2.15-2.23 Å). Theoretical investigations indicate that there is no bond between the two silicon atoms, and that the unusual geometry can be related to a significant coulomb repulsion between the two ring nitrogen atoms. This chemical pressure phenomenon could provide an alternative and superior way of squeezing out van der Waals space in highly strained structures, as compared to the classical physical methods. [ABSTRACT FROM AUTHOR]

A new stable heterocyclic germylene, in which the divalent germanium atom lies between a nitrogen atom and a phosphanylidene phosphorane group, was synthesized. Experimental and theoretical studies revealed the peculiar effect of phosphanylidene phosphorane substituent, which is a stronger π-donor towards germanium than an amino group is. Because of the weak phosphorus-germanium π-bond, this new germylene compound shows an enhanced reactivity compared to classical N-heterocyclic germylenes. [ABSTRACT FROM AUTHOR]

Dihydroxybenziphthalocyanine 1, with bulky aryloxy groups, has been synthesized and characterized by X-ray crystallography, NMR and UV/Vis-NIR spectroscopy, and theoretical calculations. Macrocycle 1 is the first example of an aromatic benziphthalocyanine with an 18π-electron structure, and was found to exist as an equilibrium mixture of weakly aromatic and strongly aromatic tautomers. The aromaticity and near-IR absorption can be controlled by chemical modification at the reactive resorcinol moiety and by variation of the solvent. [ABSTRACT FROM AUTHOR]