Synthesis and Coordination Complexes of Bis-Pocket Siloxyporphyrins

A high yield synthetic route for an alkylthiolate-tailed bis-face protected iron porphyrin was developed. The high stability of this compound is likely due to the protection from the siloxy pocket around the thiolate tail. Very similar rhombic, high spin EPR spectra for this model compound and the P450 enzyme showed that the choice of a more basic thiolate tail is essential for model compounds to reproduce the electronic structure of the heme in P450. The single crystal x-ray structure showed that the sulfur atom is bound to the iron. The Fe-S bond distance is 2.237(7) A, and the iron is pulled out of the porphyrin plane by 0.50 A, indicating that the iron is in the high spin state. This Fe-S bond distance is very similar to the value reported for the P450 enzyme at its resting state. This is the first single crystal x-ray structure of a high spin alkylthiolate-tailed ferric porphyrin. UV-Vis and EPR spectroscopy also showed that methanol binding at low temperatures can induce the high spin to low spin transition for the thiolate-ligated iron porphyrin.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemistry

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Fang, Ming

Contributors dc:contributor

• Kenneth S. Suslick

• Chemistry, Inorganic

Language dc:language

eng

Identifier

(MiAaPQ)AAI3337773

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/84309