Catalytic Tools for Functional Molecules

The preparation of complex molecules based on a carbon framework from simple molecules (build blocks) requires synthetic tools in form of specialized chemical reactions and catalysts to facilitate such transformations. In addition, such reactions should allow the decoration of the molecules by functional groups such as alcohols, esters etc or with heteroatoms. While transition metal catalysts are often based on expensive noble metals such as iridium, rhodium or platinum, we will concentrate our efforts in this project on less expensive and less well investigated metals such as cobalt and ruthenium for such pur poses. The two classes of reactions in the centre of the project are highly atom-economical, either able to convert three alkyne molecules (building blocks containing a carbon-carbon triple bond) to aromatic molecules in one step (cyclotrimerization reaction), or to activate carbon-hydrogen (C-H) bonds for subsequent coupling of the C atom with another group or molecule. For this purpose, also ligands (molecules bound to the catalyst metal to modify its properties and reactivity) will be developed and investigated towards their ability to influence the reactions in the intended way. The molecules to be prepared will containing interesting chemical and physical properties, especially investigations towards their potential as novel ligands in catalytic reactions and in the area of photophysics are planned. They will also be investigated for their ability to modify gold surfaces for specific applications and the investigation of the behaviour of such molecules on the surface of gold. The assembly of large aromatic molecules containing heteroatoms like nitrogen as an helicene (natural existing helicenes are, e.g. DNA) and deposition of such molecules on metal surfaces and addition of energy can lead to the formation of large planar organic molecules, whose interesting properties will also be investigated within the project by cooperation with physicists.