Synthesis and Structure of a Trigonal Monopyramidal Fe(II) Complex and Its Paramagnetic Carbon Monoxide Derivative

摘要

We report the isolation and structural characterization of an Fe(H) complex containing a trigonal monopyrarnidal coordination geometry. Trigonal moraopyramidal coordination to a metal ion is rate and, to our knowledge, has not been observed previouslyfor Fe(II) ions. To stabilize this coordination geometry, the tripodal ligand, tris-(N-isopropylcarbamoylmethyl)amine (H_31~(iPr)), was synthesized consisting of a tertiary amine and three deprotonated amides with appended isopropyl groups. These isopropyl groups are designed to limit access of exogenous ligands to the Fe(II) center. This constrained microenvkonment can lead to iron adducts with new structural and physical properties, as is illustrated by the formation of a paramagnetic Fe(II)--carbonmonoxide complex.