Synthesis and Characterization of Iron Trisphenolate Complexes with Hydrogen-Bonding Cavities

A new family of C 3-symmetric ligands, featuring phenolate donors and a secondary coordination sphere, have been synthesized. We report the synthesis and subsequent coordination chemistry of these new tripodal N-anchored tris(phenolate) chelates, [tris(5-tert-butyl-3-N-carboxamide-2-hydroxybenzyl)amines] (H3 RSalAmi), to iron(II), iron(III), and zinc(II). These electron-rich complexes have intramolecular hydrogen bonds, and therefore the potential to stabilize biologically relevant substrates in small-molecule activation chemistry.