Surprising Substituent Effects on the Self-Assembly of Helicates fromBis(bipyridyl) BINOL Ligands

摘要

A number of different bis(bipyridyl) BINOL ligands were prepared using a convergent building blockapproach. These were studied with regard to their ability to undergo self-assembly to dinuclearhelicates upon coordination to suitable late-transition-metal ions. Surprisingly, the substituents atthe periphery of the ligand structure were found to have a marked influence on the outcome of theself-assembly processes with regard to the helicates composition, the stereoselectivity of the helicateformation, their redox reactivity, and their electronical properties as scrutinized by NMR- andCD-spectroscopic methods as well as ESI-mass spectrometric methods.