Structure and Conformation of Individual Molecules upon Adsorption of a Mixture of Benzoporphyrins on Ag(111), Cu(111), and Cu(110) Surfaces

The front cover artwork is provided by the groups of Prof. Dr. Hans-Peter Steinrück and Prof. Dr. Norbert Jux at the Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg. The image shows a mixture of six 2H-tetrakis-(3, 5-di-tert-butyl-phenyl)(x)benzoporphyrins (2H-diTTBP(x)BPs, x = 0, 1, 2-cis, 2-trans, 3, or 4) molecules forming a porous square structure on Ag(111) as observed in scanning tunneling microscopy (STM) at room temperature. Read the full text of the Research Article at 10.1002/cphc.202300355 .     

Formation and Surface Behavior of Pt and Pd Complexes with Ligand Systems Derived from Nitrile-functionalized Ionic Liquids Studied by XPS

We studied the formation and surface behavior of Pt(II) and Pd(II) complexes with ligand systems derived from two nitrile-functionalized ionic liquids (ILs) in solution using angle-resolved X-ray photoelectron spectroscopy (ARXPS). These ligand systems enabled a high solubility of the metal complexes in IL solution. The complexes were prepared by simple ligand substitution under vacuum conditions in defined excess of the coordinating ILs, [C₃CNC₁Im][Tf₂N] and [C₁CNC₁Pip][Tf₂N], to immediately yield solutions of the final products. The ILs differ in the cationic head group and the chain length of the functionalized substituent. Our XPS measurements on the neat ILs gave insights in the electronic properties of the coordinating substituents revealing differences in donation capability and stability of the complexes. Investigations on the composition of the outermost surface layers using ARXPS revealed no surface affinity of the nitrile-functionalized chains in the neat ILs. Solutions of the formed complexes in the nitrile ILs showed homogeneous distribution of the solute at the surface with the heterocyclic moieties preferentially orientated towards the vacuum, while the metal centers are rather located further away from the IL/vacuum interface.     

Telechelic Polyisobutenes with Asymmetrical Reactivity

3-Chlorocyclopentene-(1) has been used as initiator in the quasiliving cationic polymerization of isobutene. Polyisobutenes in the molecular weight range Mw = 300 - 60000 Dalton with a molecular weight distribution MWD between 1.17 and 1.34 have been synthesized. The linear polymer was selectively hydrosilated on one or both ends. With a furan coupling agent, the PIB (polyisobutene) was dimerized, yielding polymers with a cyclopentene head- and tail group.