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The article focuses on the crystal structures of 2-[(4-flourophenyl)iminomethyl]-pyrrole and 2-[(1H-pyrrol-2-ylmethylidene)-amino]benzonitrile. Pyrrole and its substituted derivatives are five-membered heterocyclic compounds that are used in the applications of anion-binding systems, bioactive molecules and pharmaceuticals. The structures consist of two independent molecules in a asymmetric unit that form dimers through N-H···N hydrogen bonds.

The article presents a paper about trans-Chlorido(phenyl)bis(triphenyl-phosphine)nickel(II) and its 1:1 cocrystal with chloridobis(triphenyl-phosphine)nickel(I). It mentions the interest attracted by a new class of neutral nickel catalysts based on salicylaldimine or anilinotropone ligands. A view of the crystal packing of cocrystal (3) along c, showing the alternating layers along a is provided.

The article discusses a study which compares and discusses the crystal structures and supramolecular arrangements of the metal-organic compound, tetra-μ-acetato-bis{[1,3-bis(2,6-diiso-propylphenyl)imidazol-2-ylidene]-rhodium(II)}(Rh-Rh) tetrahydro-furan tetrasolvate and toluene trisolvate. It cites that the molecular structures of the two complex molecules show a similar conformation, but due to the presence of various solvent molecules, the two solvates crystallize in different space groups and display quite diverse supramolecular assemblies.

The title compound, [1,2-bis(diphenylphosphino)ethane](η5-cyclo­penta­dienyl)(4-nitro­benzonitrile)iron(II) iodide, [Fe(η5-C5H5)(C7H4N2O2)(C26H4P2)]I, crystallizes in the non-centrosymmetric space group Cc, which is a promising result for obtaining quadratic non-linear optical properties. However, the packing shows that the iodide counter-ion promotes the cancellation of almost all the dipoles, resulting in a supra­molecular motif of cationic chains aligned in opposite directions making an angle of 35.2°. The use of PF6− as counter-ion induces the crystallization of the complex in a centrosymmetric space group. These results show that the introduction of different counter-ions, of different size and geometry, allows specific and directional inter­molecular inter­actions that can determine the formation of a particular type of crystal packing. [ABSTRACT FROM AUTHOR]

The structure of the title compound, [Ti(C2H6N)2(C6H8N)Cl], displays a η5 -coordination mode for the pyrrolyl ring, confirmed by the values of the slip parameter [0.073 (9) Å and the fold angle [4.6 (6)°]. This coordination is confirmed by NMR data, which point to the involvement of the complex in a fluxional process in solution above 285 K, passing through an intermediate involving simultaneously a metal-azaallyl and a metal-olefin bond. [ABSTRACT FROM AUTHOR]

In the title complex, trans-{2,2′-[cyclo­hexane-1,2-diyl­bis­(ni­t­rilo­methyl­idyne)]­di­phenol­ato-κ4 O, N, N′, O′}­nickel(II)-chloro­form (1/1), [Ni(C20H20N2O2)]·CHCl3, the Ni atom has a square-planar geometry, slightly tetrahedrally distorted. The Ni-N and Ni-O bonding distances are within the expected ranges for Ni-Schiff base derivatives. The di­imine bridge has a gauche conformation with the cyclo­hexyl ring almost coplanar with the NiN2O2 plane. The complex mol­ecules pack in dimers with an Ni⃛Ni distance of 3.59 (1) Å and form a three-dimensional structure displaying a herring-bone configuration. Channels are occupied by solvent mol­ecules, which are involved in C-H⃛O hydrogen bonds with the ligand O atoms. [ABSTRACT FROM AUTHOR]

A second polymorphic form (form II) of the previously reported 1,4,7-tris( p-tolylsulfonyl)-1,4,7-triazacyclononane (form I), C27H33N3O6S3, is presented. The molecular structures of the two forms display very different conformations, thus prompting the two forms to crystallize in two different space groups and exhibit quite diverse crystal structure assemblies. Form I crystallizes in the triclinic space group P , while form II crystallizes in the monoclinic space group P21/ n. The main differences between the two molecular structures are the conformations of the p-tosyl groups relative to each other and to the macrocyclic ring. The resulting crystal packing displays no classical hydrogen bonds, but different supramolecular synthons give rise to different packing motifs. [ABSTRACT FROM AUTHOR]

The title compound, (η5-cyclo­penta­dienyl)(4-nitro­benzo­nitrile-κ N)(trimethyl­phosphine-κ P)(triphenyl­phosphite-κ P)iron(II) hexa­fluoro­phosphate, [Fe(C5H5)(C7H4N2O2)(C18H15O3P)(C3H9P)]PF6, has been characterized by spectroscopic and X-ray diffraction in order to evaluate the tuning of the electron density at the metal centre and the extension of the π delocalization on the mol­ecule due to the presence of phosphite and phosphine co-ligands. The compound crystallizes in the centrosymmetric space group P21/ c, which destroys the possibility of exhibiting any quadratic non-linear optical properties. The packing shows a supramolecular zigzag chain of antiparallel cations connected via the PF6− anions through C—H⋯Fδ− inter­actions, with H⋯F distances ranging from 2.39 to 2.67 Å. Each zigzag chain is composed of isomeric organometallic fragments containing either R or S mol­ecules. These chains are connected through weak inter­molecular C—H⋯C inter­actions, forming a two-dimensional plane parallel to (101). [ABSTRACT FROM AUTHOR]