Crystal structure of tris-(1,10-phenanthroline-κ(2) N,N')iron(II) bis-[bis-(tri-fluoro-methyl-sulfon-yl)imide] monohydrate

Abstract

The crystal structure of the title complex, [Fe(C12H8N2)3][(CF3SO2)2N]2·H2O, is constructed by one octa-hedral [Fe(phen)3](2+) (phen = 1,10-phenanthroline) cation (point group symmetry 2), two Tf2N(-) [bis-(tri-fluoromethyl-sulfon-yl)imide] anions, and one water mol-ecule of crystallization (point group 2). The Fe-N bond lengths are indicative of a d (6) low-spin state for the Fe(II) ion in the complex. The dihedral angle between the phen ligands in the cation is 87.64 (6)°. The Tf2N(-) counter-anion is non-coordinating, with the -CF3 groups arranged in a trans fashion with respect to each other, leading to an anti,anti conformation of the -CF3 groups and -SO2N- moieties relative to the S-C bonds. The water mol-ecule of crystallization connects two O atoms of the Tf2N(-) anions through weak hydrogen bonds. C-H⋯O hydrogen-bonding inter-actions are also observed, consolidating the packing of the mol-ecules into a three-dimensional network structure.

Keywords: 1,10-phenanthroline; bis­(tri­fluoro­methyl­sulfon­yl)imide; complex salt; crystal structure; hydrogen bonding; iron(II) complex; low-spin d6 FeII ions.

Fig. 1.

View of the [Fe(phen)3]2+, Tf2N- and H2O molecular units. Displacement ellipsoids are represented at the 30% probability level. Hydrogen atoms were omitted for clarity. [Symmetry code: i) -x + 1,y,-z + 1/2.]

Fig. 2.

Hydrogen bonds between the H2O molecule and Tf2N- anions. [Symmetry codes: ii) x - 1/2,y - 1/2,z, iii) -x + 3/2, y - 1/2, -z + 3/2.]