A new hexadentate ligand 1 was used to prepare the first FeIIFeIII complex that mimics the unsymmetrical coordination in the active site of one form of semimet hemerythrin. The different valences of the iron ions in this model complex are localized in solution, in analogy to the iron centers in the protein.

The polymerization of styrene-in-water microemulsions prepared using polymerizable cosurfactants, such as hydroxyalkyl acrylates or methacrylates, gives rise to stable suspensions of well-defined highly functionalized nanoparticles in the 15−25 nm diameter range. Among the various associations of ionic surfactants with hydroxyalkyl (meth)acrylate cosurfactants tested, the surfactant/cosurfactant system (sodium dodecyl sulfate/2-hydroxypropyl methacrylate) is found to be the most effective and allows the preparation of oil in water microemulsions of styrene (up to 7 wt %) or mixture of monomers. Polymerization with 100% conversion is achieved at room temperature using either an oil-soluble photoinitiator (DMPA) or water-soluble redox systems (hydrogen peroxide/ascorbic acid or ammonium persulfate/diamine). GC monitoring of conversion for both monomers clearly demonstrates that the mechanism of copolymerization depends on the location of the reactive species (monomer, polymerizable cosurfactant, and radical initiator). The resulting polymers contain up to 40% of hydroxylated units.

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The structure and the magnetic and electrochemical properties of the active center of purple acid phosphatases are modeled by a complex that mimics the terminal coordination of the tyrosine residue and was prepared with a new heptadentate phenola‐to ligand system. The instability of the reduced FeIIFeII state of the enzyme may be attributed to the terminal ligand, since the phenolato ligand in the model is a destabilizing factor.