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Abstract: In this Letter, we present a synthetic and structural study into bis-imino substituted diiminoisoindolines, which can be synthesized either via CaCl2 mediated reaction of phthalonitrile with primary amines, or via direct reaction of these amines with unsubstituted diiminoisoindoline. The preferred synthesis does depend on the methodology, and in two cases singly substituted adducts were formed. The single crystal X-ray structures show that, with the exception of the bis-naphthyl compound, the anti conformation is preferred, and that the ionizable hydrogen atom resides on an exocyclic nitrogen rather than the central isoindoline nitrogen atom. [Copyright &y& Elsevier]

The crystal structures of six cobalt sandwich complexes—four in the η5-cyclopentadienyl/η4-cyclobutadiene family, two from the related η5-cyclopentadienyl/η4-cyclopentadienone family—are presented and discussed alongside related structural precedents. In each of the complexes an undecorated cyclopentadienyl ligand is present whereas the partner cyclobutadiene or cyclopentadienone ligand bears four identical aromatic substituents (phenyl, p-tolyl, p-fluorophenyl, 2-thienyl or 2,2′-bithienyl). This range of substituents allows for detailed structural comparison between members of the families of sandwich complexes presented here, and with previously reported structures. Crystal structures of members of the η5-cyclopentadienyl/η4-tetraarylcyclobutadiene (left) and η5-cyclopentadienyl/η5-cyclopentadienone (right) families of sandwich complexes are presented. [ABSTRACT FROM AUTHOR]

We present the synthesis of several azadipyrromethenes with four peripheral arene units which can be readily generated via the well-established chalcone synthetic method. The stability and yields of these azadipyrromethenes is highly dependent on the nature of the arene substituent, with the bis-pyridine systems exhibiting the highest degree of instability. The structures of several of the compounds and their BF 2 adducts are presented; intramolecular hydrogen bonding is observed in the free base ADPMs. We also present a study into the absorption and emission properties of the ADPMs and their BF 2 adducts and observe that they are also highly dependent on the identity of the substituents. [ABSTRACT FROM AUTHOR]

The reaction of [Re(CO)3(H2O)3]Br or [Re(CO)5Cl] with two peptides, glycylglycine, or glycylalanine were investigated. Each reaction produced a unique, well-defined product. Structural elucidation showed the formation of chiral compounds with the formula [Re(CO)3(Gly-Xxx-O)]2, Xxx = Gly ( 1), Ala ( 2). Each dimer displays C2 symmetry and a nearly rectangular shape. The ligands are bound through the amine and amide carbonyl at a rhenium center and through the pendant carboxylate to the adjacent rhenium center. Both products are fully characterized by X-ray structure elucidation. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis of 1,8-dithia-4,11-diazacyclotetradecane L3 , a member of a series of [14]aneN2S2 ligands, has been synthesized and characterized. The crystal structures of [1,8-dithia-4,11-diazacylotetradecane] L3 and [1,8-dithia-4,11-diazayclotetradecane dihydrochloride] L3·2HCl are presented. [Copyright &y& Elsevier]