This theses presents the synthesis and characterization of Cd(II)-, Pb(II)- and Hg(II)-aminoethanethiolates in aqueous media. 2-Aminoethanethiolate, a versatile sulfur andnitrogen (S/N) based ligand was used due to its resemblance to the naturally occurringamino acid, cysteine. The work is presented in four major parts: first, backgroundinformation on the versatile structural chemistry of Cd, Pb and Hg-thiolates with S/Ncontaining ligands; second, synthesis and characterization of Cd(II) with 2-aminoethanethiolates; third, synthesis and characterization and structural chemistry ofPb(II) with 2-aminoethanethiolates; and fourth, synthesis and characterization of Hg(II)-2-aminoethanethiolates in solution- and solid-state with emphasis on the mechanisticpathways for the formation of clusters.The compounds reported here are synthesized by direct addition of the metal saltsand the ligand in deionized water. For Cd(II)-thiolates, insoluble products (77 - 80 and 82- 84) due to the formation of oligomers and polymers were obtained. In Pb(II)-thiolates(85 - 89), the structural chemistry is variable due to the extensive array of coordinationenvironments Pb can acquire. This can be related to the stoichiometry of the reaction aswell as the reaction conditions. The structural trends in Cd(II)- and Pb(II)-thiolates arenot observed in the Hg(II)-thiolates. Rather the halide influences the formation ofmolecular as well as non-molecular structures. Systematic pathways for the formation ofthe compounds based on a variety of commonly observed structural 'building blocks' arepresented. For Cl, Br derivatives, a four-coordinate intermediate, [Hg(SR)2X2] (88 - 96)and for I derivatives three-coordinate intermediates, [HgI(SR)2] and [HgI2(SR)] (97 -100) can be considered as building units. The compounds were characterized withIR/Raman, NMR, MS, Uv-Vis and X-ray crystallography.

The reaction between deprotonated 1,3-Bis(3-acetylphenyl)triazene and Hg(CH3COO)2 in methanol, yields [Hg(RNNNR)(Py)] (R=3-CH3C(O)C6H4) (1), a triazenide dimeric mononuclear complex of mercury(II). The crystal structure analysis of (1) reveals a bi−dimensional supramolecular arrangement as result of molecular self-assembly provided by Hg−η², η² −arene π interactions, and C−H···O non−classical hydrogen bonding. The crystal system of (1) is monoclinic and belongs to the space group P21/c with the cell parameters a = 13,8647(5), b = 14,8823(5), c = 17,0403(5) Å, and β = 92,2140(10)°. The crystal structure refinement achieves the final indexes R1 = 0,0440 and wR2 = 0,1034. Deprotonated 1,3-Bis(3-acetylphenyl)triazene reacts with Cu(CH3COO)2·2H2O in methanol yielding [Cu(RNNNR)2]2 (R = 3−CH3C(O)C6H4) (2), a binuclear triazenide complex showing a lantern −type molecular structure. The crystal structure of (2) reveals that molecules of the complex do not suffer intermolecular interactions. The Cu···Cu distance [2,4056(9)Å] give rise to the interpretation of an inter-metallic interaction supported by an anti−ferromagnetic coupling between the Cu(II) ions. The crystal system of (2) is triclinic and belongs to the space group P(-1) with the cell parameters a = 10,1977(11), b = 15,5390(19), c = 19,173(2) Å, α = 92,960(3)°, β = 90,484(4)°, and у = 100,997(3)°. The crystal structure refinement achieves the final indexes R1 = 0,0572 and wR2 = 0,1197. Beside the single−crystal X−ray structural analysis, both the complexes of (1) and (2) were characterized by infra-red vibrational spectroscopy and UV/VIS electronic transition spectroscopy. / A reação entre o 1,3-bis(3-acetilfenil)triazeno desprotonado e o Hg(CH3COO)2 em metanol, produz [Hg(RNNNR)(Py)] (R=3-CH3C(O)C6H4) (1),um complexo mononuclear dimérico triazenídico de mercúrio(II). A análise da estrutura cristalina de (1) revela um arranjo supramolecular bidimensional como o resultado de um auto-arranjo molecular através de interações Hg-η² , η² - areno π, , e por ligações de hidrogênio não-clássicas C-H H .O sistema de cristalino do (1) é monoclínico e pertence ao grupo espacial P21/c com os parâmetros de cela a = 13,8647 (5), b = 14,8823 (5), c = 17,0403 (5) Å, e β = 92,2140(10)°. O refinamento da estrutura cristalina apresenta os índices do finais R1 = 0,0440 e wR2 = 0,1034. O 1,3-bis(3-acetilfenil)triazeno desprotonado reage com o Cu(CH3COO)2.2H2O em metanol que produz o [Cu(RNNNR)2]2 (R = 3−CH3C(O) ) (2), um complexo triazenídico binuclear que mostra um estrutura molecular do tipo lanterna . A estrutura cristalina de (2) revela que as moléculas do complexo não sofrem interações intermoleculares. A distância Cu···Cu [2,4056(9)Å] causa a interpretação de uma interação inter-metálica resultado de um acoplamento anti-ferromagnético entre os íons do Cu(II). O sistema cristalino de (2) é triclínico e pertence ao grupo espacial P(-1) com os parâmetros de cela a = 10,1977 (11), b = 15,5390 (19), c = 19,173 (2) Å, α = 92,960(3)°, β = 90,484(4)°, e у = 100,997(3)°. A estrutura cristalina refinada alcança os índices finais R1 = 0,0572 e wR2 = 0,1197. Além da análise da estrutura do monocristal de (1) e (2), ambos foram também analisados por espectroscopia no infravermelho e UV-Vis.

The results of this study show that novel mesoporous carbons were obtained as inverse replica of SBA-15, HMS and MCM-41 silica templates, with a large pore diameter (2-4 nm), a BET surface area of 1867, 874 and 910 m2g –1 respectively for CA_SBA-15_LPG_105, CA_HMS_LPG_80 and CA_MCM- 41_LPG_80 with bimodal pore size distribution (PSD) in the mesopores range. The results obtained show that mesoporous carbon with graphitic structures can be synthesized via the LPG route.

The results of this study show that novel mesoporous carbons were obtained as inverse replica of SBA-15, HMS and MCM-41 silica templates, with a large pore diameter (2-4 nm), a BET surface area of 1867, 874 and 910 m2g –1 respectively for CA_SBA-15_LPG_105, CA_HMS_LPG_80 and CA_MCM- 41_LPG_80 with bimodal pore size distribution (PSD) in the mesopores range. The results obtained show that mesoporous carbon with graphitic structures can be synthesized via the LPG route.

Philosophiae Doctor - PhD / The results of this study show that novel mesoporous carbons were obtained as inverse replica of SBA-15, HMS and MCM-41 silica templates, with a large pore diameter (2-4 nm), a BET surface area of 1867, 874 and 910 m2g–1 respectively for CA_SBA-15_LPG_105, CA_HMS_LPG_80 and CA_MCM- 41_LPG_80 with bimodal pore size distribution (PSD) in the mesopores range. The results obtained show that mesoporous carbon with graphitic structures can be synthesized via the LPG route. / South Africa

<p style="text-align: justify; ">Reactions of 3,5-dimethylpyrazole-1-carboxamidinium&nbsp;nitrate (dpca∙HNO3) and 4-acetyl-3-amino-5-methylpyrazole (aamp) with transition metals under different reaction conditions are presented. The template reaction of aamp with triethyl orthoformate (teof) in the presence of metal ion is described. Besides, condensation of aamp with thiosemicarbazide (tsc) and the coordination of its product to copper(II) ion is also described. Twelve new complex compounds are synthesized and fully characterized. The characterization of two other, already known complexes is significantly enriched. The influence of HSAB interactions between the metal ions and ligators on the structures of obtained compounds is studied. The influence of the reaction conditions on the composition, structure and quality of crystals obtained in the reactions is investigated. Compounds are characterized by structural&nbsp;analysis, elemental analysis, molar conductivity data, infrared spectrometry and thermal analysis. Some selected complexes are characterized by UV-Vis spectra, magnetic measurements and biological activity tests, too.</p> / <p> Reactions of 3,5-dimethylpyrazole-1-carboxamidinium&nbsp;nitrate (dpca∙HNO3) and 4-acetyl-3-amino-5-methylpyrazole (aamp) with transition metals under different reaction conditions are presented. The template reaction of aamp with triethyl orthoformate (teof) in the presence of metal ion is described. Besides, condensation of aamp with thiosemicarbazide (tsc) and the coordination of its product to copper(II) ion is also described. Twelve new complex compounds are synthesized and fully characterized. The characterization of two other, already known complexes is significantly enriched. The influence of HSAB interactions between the metal ions and ligators on the structures of obtained compounds is studied. The influence of the reaction conditions on the composition, structure and quality of crystals obtained in the reactions is investigated. Compounds are characterized by structural<br /> analysis, elemental analysis, molar conductivity data, infrared spectrometry and thermal analysis. Some selected complexes are characterized by UV-Vis spectra, magnetic measurements and biological activity tests, too</p>