Eisen- und Mangankomplexe für die Untersuchung superoxidrelevanter Prozesse [Elektronische Ressource] = Iron and manganese complexes for investigation of superoxide relevant processes / vorgelegt von Anna Katharina Dürr

Katharina Dürr

Informations

• Publié par: friedrich-alexander-universitat_erlangen-nurnberg
• Publié le: 01 janvier 2010
• Nombre de lectures: 36
• Langue: Deutsch
• Poids de l'ouvrage: 16 Mo

Extrait

Eisen- und Mangankomplexe für die Untersuchung
superoxidrelevanter Prozesse

Iron and Manganese complexes for investigation of
superoxide relevant processes





Der Naturwissenschaftlichen Fakultät der Friedrich-Alexander-Universität Erlangen-
Nürnberg
zur Erlangung des Doktorgrades



2010



vorgelegt von
Anna Katharina Dürr


aus Frankfurt am Main

Als Dissertation genehmigt von der Naturwissenschaftlichen Fakultät der Universität
Erlangen-Nürnberg























Tag der mündlichen Prüfung: 18.05.2010

Vorsitzender der Promotionskommission: Prof. Dr. E. Bänsch

Erstberichterstatterin: Prof. Dr. I. Ivanović-Burmazović

Zweitberichterstatter: Privatdozent Dr. N. Jux



Mein besonderer Dank gilt meiner Doktormutter Prof. Dr. Ivana Ivanović-
Burmazović ebenso wie Prof. Dr. Rudi van Eldik für das interessante
Themengebiet, die offene Atmosphäre, die abwechslungsreiche Arbeit und die
große akademische Freiheit und Gestaltungsmöglichkeit.



























Die vorliegende Arbeit entstand vom Dezember 2006 bis zum Dezember 2009
am Institut für Bioanorganische Chemie der Friedrich-Alexander Universität
Erlangen-Nürnberg.










Chor
Es ist vorbei.

Mephistopheles
Vorbei! Ein dummes Wort.

Faust II, J. W. von Goethe










Table of contents
1.   Introduction............................................................................... 1  
1.1.   Superoxide and its chemical and biochemical properties......... 1  
1.2.   Iron peroxo and superoxo species in biological systems......... 4  
1.3.   Stoichiometric reaction of heme systems with superoxide ...... 6  
1.3.1.   Stoichiometric reaction of iron porphyrins with superoxide and
production of a peroxo complex ..............................................................6  
1.3.2.   Porphyrins as ditopic receptors.............................11  
1.4.   Catalytic reaction of superoxide with non-heme systems....... 13  
1.5.   Stopped-flow kinetics.................................................................. 14  
2.   Aims ......................................................... 17  
3.   Results and discussion.......................................................... 18  
3.1.   Heme systems and their reaction with superoxide .................. 18  
3.1.1.   Heme model systems used...................................18  
3.1.1.1.   Metalation of porphyrin ligands..........................................................19  
III III3.1.1.2.   Speciation of [Fe (TBuTPP)Cl] (12) and [Fe (Porph)Cl] (13) in DMSO
solution .............................................................20  
III III3.1.1.3.   ESI mass spectrometry of [Fe (TBuTPP)Cl] (12) and [Fe (Porph)Cl]
(13) in DMSO solution.......................................................................27  
3.1.2.   Generation and characterization of superoxide in solution at low
concentrations and under steady state conditions39  
3.1.3.   Reaction of ligand 11 with superoxide, KOH and NaOH.......................44  
3.1.4.   Short reprise of literature background on reactions of iron porphyrins
with superoxide .....................................................................................49  
III3.1.5.   Investigation of the reaction of iron(III) porphyrins [Fe (TBuTPP)Cl] (12)
IIIand [Fe (Porph)Cl] (13) in DMSO with low concentrations of superoxide
........................................................................................................50  
3.1.5.1.   Reduction of iron(III) porphyrins by superoxide.50  
II3.1.5.2.   Reaction of [Fe (Porph)(DMSO) ] (n = 1, 2) (38) with oxygen as a n
back reaction and its side products...................................................53  
I
3.1.6.   Synthesis and solution chemistry of iron(II) porphyrins; spectroscopic
characterization.....................................................................................56  
3.1.6.1.   Design of a preparative spectroelectrochemical cell .........................57  
III3.1.6.2.   Spectroelectrochemical reduction of [Fe (TBuTPP)Cl] (12) and
III[Fe (Porph)Cl] (13) in DMSO solution ..............................................60  
3.1.6.3.   Characterization of solution chemistry of iron(II) porphyrins 37 and 38
1by paramagnetic H NMR spectroscopy...........64  
3.1.6.4.   Characterization of solution chemistry of iron(II) porphyrins 37 and 38
by Mößbauer spectroscopy...............................................................75  
3.1.6.5.   Characterization of iron(II) porphyrin 38 by EPR spectroscopy.........76  
III3.1.7.   Investigation of the reaction of iron(III) porphyrins [Fe (TBuTPP)Cl] (12)
IIIand [Fe (Porph)Cl] (13) in DMSO with excess of superoxide...............77  
3.1.7.1.   Investigation of reaction with crown ether porphyrin complex
II[Fe (Porph)(DMSO) ] (n = 1, 2) (38) .................................................78  n
3.1.7.1.1.   Reversible binding of superoxide...................78  
3.1.7.1.2.   Investigation of possible production of iron(IV) species .................81  
III3.1.7.1.3.   Reaction of hydroxo complex [Fe (Porph)OH] (18) with superoxide .
.............................................................................................85  
3.1.7.1.4.   Kinetic and thermodynamic quantification of the equilibrium..........86  
II3.1.7.2.   Investigation of reaction of [Fe (TBuTPP)(DMSO) ] (n = 1, 2) (37) with n
and without added crown ether.........................................................96  
II3.1.7.3.   Comparison of reaction of [Fe (Porph)(DMSO) ] (n = 1, 2) (38) and n
II[Fe (TBuTPP)(DMSO) ] (n = 1, 2) (37) with superoxide .................106  n
III 2-3.1.8.   Characterization of the peroxo species K[Fe (Porph)(O )] (42) .......108  2
3.1.9.   DFT calculations..................................................................................136  
3.2.   Non-heme systems.... 143  
3.2.1.   Investigated complexes.......................................................................143  
3.2.2.   Investigations concerning the NO dismutase activity of seven-coordinate
manganese(II) pentaazamacrocyclic complexes145  
3.2.3.   Investigations concerning the superoxide dismutase activity of acyclic
IIseven-coordinate manganese(II) complex [Mn (Dcphp)(MeOH) ] (61) .... 2
......................................................................................................149  
3.2.4.   Acyclic five-coordinate complexes ......................................................152  
4.   Summary/ Zusammenfassung............. 166  
II
5.   Experimental ......................................................................... 174  
5.1.   General remarks......... 174  
5.2.   Routine IR and mass measurements and elemental analysis174  
5.3.   UV/vis measurements................................................................ 175  
5.3.1.   Technical specifications......175  
5.3.1.1.   Measurements under normal pressure............175  
5.3.1.2.   High pressure measurements .........................................................175  
5.3.2.   Equilibrium measurements..................................175  
5.3.3.   Preparation of superoxide solutions....................176  
5.3.4.   Preparation of solutions for UV/vis study of H Porph (11) with several 2
bases and KO ....................................................................................176  2
5.3.5.   Determination of superoxide concentration in DMSO .........................177  
5.3.6.   Test for of iron(IV) species with MCPBA.............177  
5.3.7.   High pressure UV/vis measurements..................................................177  
5.4.   ESI mass spectrometry ............................................................. 178  
5.4.1.   Technical specifications......................................178  
5.4.2.   Solution preparations..........178  
5.5.   Kinetic measurements............................................................... 179  
5.5.1.   Technical specifications......................................179  
5.5.1.1.   Rapid scan stopped-flow kinetics....................179