Two coordinate iron(II) primary amides showing high internal hyperfine fields

INOR 193

W. Alexander Merrill, Department of Chemistry, University of California - Davis, One Shields Avenue, Davis, CA 95616, William M. Reiff, w.reiff@neu.edu, Department of Chemistry, Northeastern University, 360 Huntington Ave, Boston, MA 02115, James C. Fettinger, jcfettinger@ucdavis.edu, Department of Chemistry, University of California, Davis, and Philip P. Power, Department of Chemistry, University of California - Davis, One Shields Avenue, Davis, CA 95616.
Reaction of the sterically encumbered amines [2,6-Mes2C6H3]NH2 (Mes = 2,4,6-Me3C6H2) and [2,6-Trip2C6H3]NH2 (Trip = 2,4,6-iPr3C6H2) with .6 eq Fe[N(SiMe3)2]2 in hot toluene affords the first two-coordinate monomeric iron(II) primary amides [(2,6-Mes2C6H3)NH]2Fe (1) and [(2,6-Trip2C6H3)NH]2Fe (2), respectively. Both dark red in color, (1) displays an N-Fe-N angle of 141 degrees, while (2) shows linear coordination (N-Fe-N = 180 degrees) and local C2h symmetry at iron. Mössbauer and SQUID studies of these compounds reveal high internal hyperfine fields owing to the large orbital contribution in the absence of Jahn-Teller distortion, as well as long (ca. 10 Å) intermolecular iron-iron distances which slow relaxation. Bent compound (1) undergoes significant quenching of the orbital contribution due to its lower symmetry and virtual ligation by the flanking aryls of the ligand.
 

Coordination Chemistry: Synthesis
7:00 PM-10:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, 11 September 2006 Moscone Center -- Hall D, Sci-Mix

Division of Inorganic Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006