Palladium Catalysis in Directed C-H Bond Activation and Cycloisomerisation Reactions

Abstract: The main focus of this thesis concerns the development of Pd(II)-catalysed synthetic methodologies for the preparation of biologically active compounds.In the first part (paper I-III), unactivated C–H bonds of a cyclobutane derivative are selectively functionalised using a directing group starting from the feedstock compound verbenone (paper I). In the following part the development of an efficient transamidation protocol for the directing group removal is reported (paper II). Both procedures were then used in conjunction, for the synthesis of diverse C-3 arylated benzofuran-2-carboxylamides, in only 3 steps starting from benzofuran-2-carboxylic acid (paper III).The second part (paper IV-V) aimed to evaluate the catalytic efficiency of the heterogeneous catalyst Pd(II)-AmP-MCF in the intramolecular hydroamination of propargylic carbamates. The catalyst was able to promote the formation of various 1,3-oxazolidin-2-ones in high yields, at room temperature with low palladium loadings (paper IV). This investigation is followed by a mechanistic study of the Pd(II)-AmP-MCF catalyst’s deactivation process during a lactone formation, using X-ray absorption spectroscopy (paper V).