A Convenient Way to Novel Fe~(IV) Complexes with Mixed N/S/P Coordination Spheres and 'Innocent' Ligands

摘要

Iron complexes with high-valent Fe~(IV) centers are discussed as reactive intermediates in numerous enzymatic processes that are catalyzed, for instance, by heme peroxidase, cytochrome P450, methane monooxygenase, ribonucleotide reductase, isopeni-cillin N synthase, and other enzymes. The diversity of these reactions suggests that also a rich nonbiological Fe~(IV) chemistry should be accessible. However, only a few ligands proved to be sufficiently oxidation resistant and able to stabilize Fe~(IV) centers. These ligands are mainly tetrapyrrolic ligands and other N_4 donor ligands or ligands with sulfur donors. We have now obtained Fe~(IV) complexes with a mixed N/S/P coordination sphere from readily accessible starting materials in a remarkably easyway. The one-pot reaction according to Equation (1) yields the Fe~(IV) complexes [Fe~(IV)(PR_3)(L)] in yields of more than 85%.