Layered 2D Sheetlike Supramolecular Polymers Formed by O–H···Anion Hydrogen Bonds

A hexahydroxyterphenyl was prepared in two steps and 77% overall yield. Co-crystallization of this ligand with a range of tetrabutylammonium salts gave [2 + 2] supramolecular macrocycles assembled through O–H···anion hydrogen bonds. These macrocycles form 2D sheetlike architectures through intermolecular hydrogen bonds between phenol groups. Bulk samples of these structures were prepared in high yields (70–100%) and were characterized by X-ray crystallography, ¹H NMR spectroscopy, IR spectroscopy, and elemental analysis. The relatively predictable organization of these molecules in the solid state may be exploited for crystal engineering

Layered 2D Sheetlike Supramolecular Polymers Formed by O–H···Anion Hydrogen Bonds

A hexahydroxyterphenyl was prepared in two steps and 77% overall yield. Co-crystallization of this ligand with a range of tetrabutylammonium salts gave [2 + 2] supramolecular macrocycles assembled through O–H···anion hydrogen bonds. These macrocycles form 2D sheetlike architectures through intermolecular hydrogen bonds between phenol groups. Bulk samples of these structures were prepared in high yields (70–100%) and were characterized by X-ray crystallography, ¹H NMR spectroscopy, IR spectroscopy, and elemental analysis. The relatively predictable organization of these molecules in the solid state may be exploited for crystal engineering

Controlling Ligand Exchange through Macrocyclization

Ligand exchange at a sterically hindered palladium center was investigated for six different ligands. The palladium atom was coordinated to a tridentate, NNN pincer bis­(amido)­pyridine macrocycle to produce a square-planar complex, in which an acetonitrile molecule occupies one of the coordination sites. Kinetic studies showed that ligand exchange at the palladium center proceeds through an associative mechanism and, as a consequence, is impeded by the small size of the metallomacrocycle cavity. The ligand-exchange rate on the palladium center between acetonitrile and six different ligands has been investigated and compared to the exchange rate on the corresponding open form. Our results demonstrate that macrocyclization of ligands is a way to modify the rate of guest exchange in a square-planar metal complex

[(F₆acac)Pd(μ-HNC₆F₅)]₂, a Large Family of Polymorphs and Solvates with Short F···F Contacts

Highly fluorinated [(F6acac)Pd(μ-HNC6F5)]2 was prepared by the reaction of palladium bis(hexa­fluoro­acetyl­acetonate), Pd(F6acac)2, with pentafluoroaniline. This compound generates a large family of crystalline polymorphs and solvates. In this paper, we present a study on the synthesis, solution phase dynamics, and crystal structures of highly fluorinated [(F6acac)Pd(μ-HNC6F5)]2. Pd3(μ-F6acac)2(μ-HNC6F5)4 is produced as a minor byproduct. We also describe the synthesis and structural characterization of trinuclear Pd3(μ-F6acac)3[μ-(CF3)2CN]3 prepared by the reaction of Pd(F6acac)2 with hexafluoroacetone imine