Synthesis and coordination chemistry of a potential precursor to a triarylamminium radical cation ditopic ligand

Abstract

The multi-step synthesis of a new ditopic ligand (7) is reported, which is a potential precursor to a triarylamminium radical cation. The preparation and full characterization of three new bimetallic first row transition metal [M=Mn (8), Ni (9), Cu (10)] coordination complexes containing this ligand are described, including detailed electrochemical and magnetic studies. Of note, a ground triplet state is observed in the bimetallic Cu complex. Chemical oxidation of these precursor complexes generated persistent complexes containing the dication of the ligand, which is confirmed through UV–Vis and EPR spectroscopies. The variable temperature magnetic properties of the dicationic complexes are described and included in the discussion are results from density functional theory calculations of bimetallic radical cation complexes.