Modulation of oxoiron(IV) properties through trans substitutions

INOR 947

Timothy A. Jackson, jackson@chem.umn.edu1, Jason A. Halfen, halfenja@uwec.edu2, Wonwoo Nam, wwnam@ewha.ac.kr3, and Lawrence Que Jr., que@chem.umn.edu1. (1) Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota, 207 Pleasant St. SE, Minneapolis, MN 55455, (2) Department of Chemistry, University of Wisconsin, Eau Claire, WI 54702, (3) Department of Chemistry and Division of Nano Sciences, Ewha Womans University, 11-1 Daehyun-Dong Seodaemun-Ku, Seoul 120-750, South Korea
High-valent nonheme iron-oxygen species, such as one having oxoiron(IV) units, have been proposed as key intermediates for numerous nonheme iron enzymes. Recent modeling efforts have led to the synthesis of a variety of nonheme oxoiron(IV) complexes, including the first structurally characterized member of this class, [FeIV(O)(TMC)(NCCH3)]2, where TMC is 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane. Through ligand exchange reactions and modification of the TMC ligand, related complexes with carboxylate, thiolate, and pseudohalide ligands trans to the oxo unit have been previously generated. Systematic spectroscopic studies of these compounds using electronic absorption, resonance Raman, and X-ray absorption spectroscopies reveal intriguing electronic differences, whereas EXAFS analyses suggest that, with the exception of the thiolate ligated oxoiron(IV) complex, the Fe–O distance is hardly affected by trans substitution. The reactivity properties of select oxoiron(IV) complexes will be compared.

 

Bioinorganic Modeling
1:30 PM-5:30 PM, Wednesday, 13 September 2006 Moscone Center -- Room 307, Oral

Division of Inorganic Chemistry

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