Biomedical subjects
Publications and source records attributed to Christopher J Ziegler.
Manganese N-confused porphyrins activate C-C and C-H bonds upon heating or air oxidation; the dimer complex [Mn(NCTPP)]2 is reduced at two meso positions, and the pyridine coordinated monomer breaks the internal C-H bond upon heating or exposure to oxygen.
We are using the coordinating anion tetrakis(imidazolyl)borate to construct new metal-organic framework structures. In this report, we present three alkaline earth metal network solids incorporating this anion. All three compounds have the same formula, M[B(Im)(4)](2)(H(2)O)(2) (M = Mg, Ca, Sr), and the same coordination environment about the metal. However, the three compounds have different network structures with different degrees of hydrogen bonding; the Mg material forms a two-dimensional network and the Ca and Sr compounds form one-dimensional chains. In addition, we present the structure of the protonated anion B(HIm)(Im)(3) as a model for the default structure of this anion and discuss how the conformation of tetrakis(imidazolyl)borate can affect the structure of network solids.
The coordination polymer Pb[B(Im)(4)](NO(3)), constructed by using tetrakis(imidazolyl)borate and lead(II) nitrate solutions, is a layered material with the metal centers facing the interlayer spacing. As in naturally occurring layered minerals, this compound can readily undergo anion exchange in the solid state with retention of crystallinity. We examined stoichiometric exchange of (15)N-nitrate for nitrate and iodide for nitrate by (15)N and (207)Pb SSNMR and confirmed retention of crystallinity by IR and powder XRD diffraction.
The synthesis and structural characterization of a manganese adduct of N-confused tetraphenylporphyrin (NCTPP) is presented; in the absence of coordinating ligands this complex forms a novel dimer structure and demonstrates a potential manganese agostic interaction with the interior pyrrolic CH as seen in other first row transition metal NCTPP compounds.
The anion BF(CN)3-forms isomorphous network polymers with Cu(I) and Ag(I) that exhibit one-dimensional channels along the b axis and demonstrate stability to air and light respectively.