## Files in this item

FilesDescriptionFormat

application/pdf

9010958.pdf (5MB)
(no description provided)PDF

## Description

 Title: Actinide porphyrin complexes Author(s): Milam, Stanley Nemec Doctoral Committee Chair(s): Kenneth S. Suslick Department / Program: Chemistry Discipline: Chemistry Degree Granting Institution: University of Illinois at Urbana-Champaign Degree: Ph.D. Genre: Dissertation Subject(s): Chemistry, Inorganic Chemistry, Nuclear Abstract: The first bis(porphyrin)actinide complexes have been prepared by reaction of M(NEt$\sb2$)$\sb4$ (where M = Th, U) with H$\sb2$TPP or H$\sb2$OEP. The coordination geometry of (TPP)$\sb2$Th is a distorted square-prism where the thorium center is displaced 1.47 A from each of the porphyrin N$\sb4$ planes; the porphyrin planes are separated by 2.94 A. The porphyrin macrocycles, held in such close proximity, interact electronically as shown by a shift in the porphyrin Soret band to higher energy and unusually facile oxidation processes relative to related monoporphyrin complexes.Oxidation of (TPP)$\sb2$M yields porphyrin-based radical cation complexes ((TPP)$\sb2$M$\sp+$) (SbCl$\sb6\sp-$) and dicationic complexes, ((TPP)$\sb2$M$\sp{2+}$) (SbCl$\sb6\sp-$) $\sb2$. The porphyrin planes of ((TPP)$\sb2$Th$\sp+$) (SbCl$\sb6\sp-$) are separated by 2.89 A, this separation is slightly less than that of (TPP)$\sb2$Th.The EPR spectrum of ((TPP)$\sb2$Th$\sp+$) (SbCl$\sb6\sp-$) is that of a simple organic radical (g = 2.0016) while the uranium complex shows unusual signals at g$\sb{\rm para}$ = 3.175 and g$\sb{\rm perp}$ = 1.343. SQUID measurements on ((TPP)$\sb2$Th$\sp+$) (SbCl$\sb6\sp-$) suggest that above 70 K there are thermally populated excited state(s) with f-orbital character. Above 200 K, ((TPP)$\sb2$U$\sp+$) (SbCl$\sb6\sp-$) apparently adopts S = 3/2 spin state(s), but below 70 K the spin state appears to be S = 1/2. This behavior may be due to antiferromagnetic coupling of the porphyrin radical to the f$\sp2$ U$\sp{\rm IV}$ center.The dicationic complex ((TPP)$\sb2$Th$\sp{2+}$) (SbCl$\sb6\sp-$) $\sb2$ is essentially diamagnetic. This suggests that there is a direct porphyrin-porphyrin interaction that results in a new set of molecular orbitals composed of both porphyrin ligands and perhaps some metal contribution. All of the oxidized complexes have near-IR absorptions due to transitions between these molecular orbitals.Mono(porphyrin)actinide complexes may be prepared directly from UCl$\sb4$ or ThCl$\sb4$. The uranium center of (TPP)UCl$\sb2$(thf) is displaced 1.29 A from the porphyrin macrocycle. Reaction of Na (OCH(CF$\sb3$)$\sb2$) with (TPP)UCl$\sb2$ in 1,2-dimethoxyethane (dme) yields $\{$Na(dme)$\sb3\sp+\}\{$(TPP)U (OCH(CF$\sb3$)$\sb2$) $\sb3\sp-\}$. The uranium center of this complex is displaced 1.43 A from the porphyrin macrocycle plane. Reaction of KOC$\sb6$H$\sb3$Cl$\sb2$ with (TPP)UCl$\sb2$ yields (TPP)U(OC$\sb6$H$\sb3$Cl$\sb2$)$\sb2$, which has an available coordination site and binds Lewis bases. (TPP)U(OC$\sb6$H$\sb3$Cl$\sb2$)$\sb2$ reacts with O$\sb2$ to form the first U$\sp{\rm VI}$ porphyrin complex (TPP)U(O)(OC$\sb6$H$\sb3$Cl$\sb2$)$\sb2$. This oxo complex cannot oxidize PPh$\sb3$ to OPPh$\sb3$. Issue Date: 1989 Type: Text Language: English URI: http://hdl.handle.net/2142/19431 Rights Information: Copyright 1989 Milam, Stanley Nemec Date Available in IDEALS: 2011-05-07 Identifier in Online Catalog: AAI9010958 OCLC Identifier: (UMI)AAI9010958
﻿
{"extraction_info": {"found_math": true, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 1, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0, "math_score": 0.7746168375015259, "perplexity": 20029.941805181348}, "config": {"markdown_headings": true, "markdown_code": true, "boilerplate_config": {"ratio_threshold": 0.18, "absolute_threshold": 10, "end_threshold": 15, "enable": true}, "remove_buttons": true, "remove_image_figures": true, "remove_link_clusters": true, "table_config": {"min_rows": 2, "min_cols": 3, "format": "plain"}, "remove_chinese": true, "remove_edit_buttons": true, "extract_latex": true}, "warc_path": "s3://commoncrawl/crawl-data/CC-MAIN-2017-04/segments/1484560280835.22/warc/CC-MAIN-20170116095120-00272-ip-10-171-10-70.ec2.internal.warc.gz"}