Synthesis of a New Ligand for Metal Assembly to a Selective Receptor.
Diarylphosphinic acid 2, bearing two ethylenediamine groups, was designed with the aim of assembly to form a hydrophobic cavity upon binding to metals. The new ligand was prepared in optically active form from phenylalanine by an efficient sequence which required chromatography only for the P-C bond forming steps. Versatile intermediates in the synthesis are described. Complexes of this ligand with Zn(2+) were shown to bind closely related aromatic guests bearing anionic tethered groups with 1000-fold discrimination.
Schwabacher
Alan W.
AW
Department of Chemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201.
Stefanescu
Andrei D.
AD
Rehman
Atiq ur
A