Synthesis of novel N-Heterocyclic Carbenes for chiral complexes and catalysis

The aim of my training period has been the synthesis of new chiral N-heterocyclic carbene precursors starting from camphoric diacid and the employment of imidazolium salts derived NHC as linker to dendrimers supports for organometallic catalysis. New chiral ligands are needed to develop new catalytic systems for enantioselective transformations. The new type of ligand described was developed starting from camphoric diacid, a cheap chiral molecule, following different synthetic strategies. Asymmetric functionalized chiral NHCs are readily available by methods developed and two of the precursors obtained were employed in preliminary tests with Aluminium and Palladium. An NHC derived from imidazolium salt has been investigated as linker to dendrimeric supports for tetraarylciclopentadienone-Ruthenium complexes with the aim to combine advantages of homogeneous catalysis to advantages of heterogeneous one, in particular easy recover of catalyst. The functionalized dendrimers obtained have been used in transfer hydrogenation and dehydrogenation reactions. Moreover a new class of functionalized dendrimer was obtained employing a new tetraarylciclopentadienone-Ruthenium complex with trimethyl silyl groups on cyclopentadienone ligand with the aim to change solubility of the system.