Polycyclic- and sulfurcontaining-compounds: from polycyclic hydrocarbons to thiaspherophane

This thesis contains the examination of four, in first glance, unrelated topics. However, the overarching motivation behind these subjects are the same: The Art and Challenge of Organic Chemistry. I. The first chapter deals with the design, based on theoretical principles, and preparation of unsaturated spirocyclic compounds bearing sulfur functionalities with the aim of elucidating the charge-transport properties of such molecules on the level of single molecules. In collaboration with the Group of Professor Herre van der Zant from the Delft University of Technology preliminary conductance measurements of such spirocyclic structures could be gathered. The motivation for this joint endeavor is the prospect of using such spirocyclic structures as a molecular switch for the construction of molecular electronic devices. II. The second part shows our engagement in the long tradition among organic chemist to challenge our abilities to synthesize inspiring, complex and aesthetical pleasing structures. One such structure was identified by employing predictive computational methods by the group of Professor Jean-Louis Reymond. The structure of interest was recognized as one of the last three remaining and not yet synthesized fully-cyclic C11 isomers without strain. Encouraged by this finding, we accepted the challenge to synthesize this tetracyclic saturated hydrocarbon with the molecular formula C11H16 with the proposed trivial name of trinorbornane. III. Thirdly, Thiaspherophane: A highly symmetrical structure consisting of eight benzene rings bridged over twelve sulfur atoms describing a cuboctahedron: one of the 13 Archimedean solids. This elusive molecule, predicted over 25 years ago, bears the potential of being transformed into a cryptatium. Our efforts and progress on the synthesis of thiaspherophane will be discussed. IV. Unsymmetrical disulfides are ubiquitous in the field of chemistry and at the interface with physics, where nanotechnology emerges. In this chapter, our investigation of an efficient method for the preparation of unsymmetrical disulfides will be presented Whereby the potential of this method for the formation of functional units bearing multiple unsymmetrical disulfides was assessed with the aim of using these compounds for functionalization of gold surfaces

Synthesis of trinorbornane

Herein we report the synthesis and characterisation of the until recently unreported chiral C-11 skeleton of tetracyclo[5.2.2.01,6.04,9]undecane ("trinorbornane'') which could be obtained in 7% overall yield in 9 steps. This new rigid structural type was found to be present in the computer generated Chemical Universe Data-base (GDB) and has until now no real-world counterpart

Chirality Sensing of Terpenes, Steroids, Amino Acids, Peptides and Drugs with Acyclic Cucurbit[n]urils and Molecular Tweezers

Achiral chromophoric hosts, i.e. acyclic cucurbit[ n ]urils and molecular tweezers, were found to respond with characteristic Circular Dichroism (CD) spectra to the presence of micromolar concentrations of chiral hydrocarbons, terpenes, steroids, amino acids and their derivates, and drugs in water. In favourable cases, this allows for analyte identification or for reaction monitoring

Preparation of Unsymmetrical Disulfides from Thioacetates and Thiosulfonates

A method for the transformation of organic thioacetates, a widely used functionality for the preparation of self-assembled monolayers on gold surfaces, into unsymmetrical disulfides is reported. Disulfides are readily immobilized on gold in contrast to thioacetates, which usually require a deprotection step prior to bonding to the metal surface. The potential of the method for the controlled preparation of unsymmetrical disulfides has been demonstrated with model compounds comprising several thioacetates, which were readily converted into the corresponding unsymmetrical disulfides

The Enantiomers of Trinorbornane and Derivatives Thereof

Herein, we report the synthesis of the enantiomers of trinorbornane, a tetracyclic saturated hydrocarbon with the chemical formula C11H16. The preparation of these rigid carbon scaffolds was enabled by the successful chiral separation of its tricyclic precursor, thus allowing the enantiomers to be synthesized through a reductive radical cyclization reaction. Assignment of the absolute conformation of the enantiomers was achieved through VCD experiments. Further, we report an alternative cyclization procedure providing access to hydroxyl and phenyl sulfone functionalized trinorbornanes

Chirality sensing of terpenes, steroids, amino acids, peptides and drugs with acyclic cucurbit[n]urils and molecular tweezers

Achiral chromophoric hosts, i.e. acyclic cucurbit[ n ]urils and molecular tweezers, were found to respond with characteristic Circular Dichroism (CD) spectra to the presence of micromolar concentrations of chiral hydrocarbons, terpenes, steroids, amino acids and their derivates, and drugs in water. In favourable cases, this allows for analyte identification or for reaction monitoring