Synthesis and Characterization of Novel Aminophosphine Ligands Based on Ferrocenodecaline Backbones

Abstract

Novel aminophosphine ligands for enantioselective transition metal catalysts based on different ferroceno cis- and trans-decaline backbones were synthesized and structurally characterized. Their palladium dichloride complexes were tested in the asymmetric Grignard cross coupling reaction of vinyl bromide and phenylethyl magnesium chloride, but only very low enantioselectivities were obtained. Steric strain in the aminophosphine ligands causes a severe backbone deformation and in addition leads to a slowed rotation of the respective dimethylamino group as was detected by variable temperature NMR spectroscopy.