<p>This thesis describes the synthesis, structure, equilibriaand other properties of novel thallium(III) monomeric andplatinum-bonded complexes with nitrogen donor ligandsethylenediamine, diethylenetriamine, triethylenetetramine,porphyrin, 2,2'-bipyridine and 1,10-phenanthroline in solutionand in solid.</p><p>The existence of three complexes withthe general formula[Tl(en)<sub>n</sub>]<sup>3+</sup>(n = 1-3) and their overall stability constantshave been established in pyridine. All three complexes wereidentified by their<sup>205</sup>Tl and<sup>1</sup>H NMR chemical shifts and<sup>205</sup>Tl-<sup>1</sup>H coupling constants. The formation process of thecomplexes was followed by<sup>1</sup>H NMR spectroscopy. The crystal structure of[Tl(en)<sub>3</sub>](ClO<sub>4</sub>)<sub>3</sub>was determined; the thallium(III) ion isN-coordinated in a distorted octahedral geometry. Two [Tl(dien)<sub>n</sub>]<sup>3+</sup>(n = 1-2) complexes were proved to exist insolution and the structure of the bis-complex [Tl(dien)<sub>2</sub>]<sup>2+</sup>in<i>u-facial</i>isomers was determined in solid. In addition,crystal structures of [Tl(en)<sub>2</sub>CN](ClO<sub>4</sub>)<sub>2</sub>with cyanide bridging between two Tl(en)<sub>2</sub>units forming an infinite chain structure and of[Tl(tren)<sub>2</sub>(CN)<sub>2</sub>](ClO<sub>4</sub>) with a distorted pseudo-octahedral coordinationaround thallium were determined. Thallium(III) complexes with2,2'-bipyridine and 1,10-phenanthroline have been studied inDMSO using<sup>205</sup>Tl,<sup>13</sup>C and<sup>1</sup>H NMR spectroscopy. In addition, aseven-coordinated thallium was found in the crystal structureof [Tl(bipy)<sub>3</sub>(dmso)](ClO<sub>4</sub>)<sub>3</sub>, and six-coordinated thallium in pseudo-octahedralgeometry in [Tl(phen)<sub>2</sub>Cl<sub>2</sub>](ClO<sub>4</sub>).</p><p>The solvated complex [Tl(dmso)<sub>6</sub>]<sup>3+</sup>has been prepared using concentrated aqueoussolution of Tl(ClO<sub>4</sub>)<sub>3</sub>by a solvent replacement reaction in DMSO, and thewater-free solid compound [Tl(dmso)<sub>6</sub>](ClO<sub>4</sub>)<sub>3</sub>was crystallized from DMSO. The structure of thecomplex [Tl(dmso)<sub>6</sub>]<sup>3+</sup>is a regular octahedron with the Tl-O bonddistance 2.224(3) Å. It represents an easy and secure wayto introduce water-free Tl(III) into organic phase withoutreduction.</p><p>Through several reactions, novel heteronuclear Pt-Tlcomplexes with the composition [(NC)<sub>5</sub>Pt-Tl(tpp)]<sup>2-</sup>, [(NC)<sub>5</sub>Pt-Tl(thpp)]<sup>2-</sup>, [(NC)<sub>5</sub>Pt-Tl(bipy)<sub>n</sub>](n = 1-2), [(NC)<sub>5</sub>Pt-Tl(en)<sub>n-1</sub>](n = 1-3) and [(NC)<sub>5</sub>Pt-Tl(phen)<sub>n</sub>](n = 1-2), have been synthesized in solution.Multinuclear NMR (<sup>195</sup>Pt,<sup>205</sup>Tl,<sup>13</sup>C and<sup>1</sup>H), Raman spectroscopy and X-ray diffraction dataare fully compatible with formation of unsupported Pt-Tl bondedcomplexes both in solution and in solid. The huge<sup>1</sup>J(<sup>195</sup>Pt-<sup>205</sup>Tl) spin-spin coupling constants (48-66 kHz) wereobserved by both<sup>195</sup>Pt and<sup>205</sup>Tl NMR spectroscopy in solution and they providea strong evidence of formation of the Pt-Tl bond in solution.In all six determined crystal structures of the Pt-Tl compoundsa very short Pt-Tl bond is found with distances2.6117(5)-2.6375(5) Å. The calculated values of Pt-Tlforce constants (1.38-1.91 N/cm) are characteristic for asingle metal-metal bond.</p><p>In the Pt-Tl compounds, the oxidation state of the metalions is intermediate between the stable states Pt<sup>II</sup>/Pt<sup>IV</sup>and Tl<sup>III</sup>/Tl<sup>I</sup>, respectively, and this is reflected by their<sup>195</sup>Pt and<sup>205</sup>Tl chemical shifts. It turns out that N-donorligands can really stabilize the Pt-Tl bond both in solutionand in solid. The character of the metal-metal bond anditstheoretical basis are discussed.</p><p><b>Keywords:</b>Thallium, Platinum, Cyanide, N-donor ligand,Metal-metal bond, Multinuclear NMR, Raman spectroscopy, X-raydiffraction, Equilibrium, Spin-spin coupling.</p>
| Identifer | oai:union.ndltd.org:UPSALLA/oai:DiVA.org:kth-3129 |
| Date | January 2001 |
| Creators | Ma, Guibin |
| Publisher | KTH, Chemistry, Stockholm : Kemi |
| Source Sets | DiVA Archive at Upsalla University |
| Language | English |
| Detected Language | English |
| Type | Doctoral thesis, comprehensive summary, text |
| Relation | Trita-OOK, ; 1061 |
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