Dissertations / Theses on the topic 'Group 13 elements'

This thesis describes the synthesis, structural and reaction chemistry of a number of novel gallium and indium containing species, including metal complexes featuring previously unreported gallium and indium ligand systems. The synthesis, spectroscopic and structural characterisation of the asymmetric haloindyl (n5-C5R5)Fe(CO)2In(Mes*)Br (R = H, Me) and halogallyl Cp*Fe(CO)2Ga(Mes)I complexes are reported herein, with Cp*Fe(CO)2ln(Mes*)Br representing the first example of structurally characterised asymmetric bromoindyl complex. Cp*Fe(CO)2In(Mes*)Br is a versatile substrate for the synthesis of asymmetric indyl complexes via substitution chemistry, thereby allowing the synthesis and characterisation of Cp*Fe(CO)2In(Mes*)ERn (ERn = OC6H4/Bu-4, SPh). The synthesis, spectroscopic and structural characterisation of the dihalogallyl complex Cp*Fe(dppe)Gal2 is also reported this synthesis was accomplished via photolytic displacement of the carbonyl ligands in Cp*Fe(CO)2Gal2 2 by dppe 1,2-bis(diphenylphosphino)ethane. Cp*Fe(dppe)Gal2 has proven to be versatile reagent in the generation of the asymmetric halogallyl species via substitution chemistry with retention of the iron-gallium bond, thereby allowing the synthesis and characterisation of Cp*Fe(dppe)Ga(Mes)I. The diiodogallyl complex has also been implicated in the synthesis of the first structurally characterised base-free cationic gallylene complex Cp*Fe(CO)2Gal + BAr/4 bearing a terminally bound Gal ligand which is valence isoelectronic with CO and N2. Investigations into the synthesis of molybdenum- and ruthenium-phosphine containing systems are also reported herein. Insertion of 'Gal' into metal-halogen bonds has proved to a viable synthetic route, for example in the 7 7 formation of (n-C7H7)Mo(CO)2Gal2 2. Further reaction of (n-C7H7)Mo(CO)2Gal2 2 with dppe, however, has been shown to yield (r - C7H7)Mo(CO)2Gai2 2(u-dppe). Investigation of 'Gal' insertion reactions involving ruthenium-halogen bonds have shown to yield the tetraiodogallate species CpRu(PPh3)2(u-I)Gal3 and CpRu(dppe) Gal4. The synthesis, spectroscopic and structural characterisation of the bridging halo-indanediyl complexes Cp*Fe(CO)2 2lnX (X = Br, I) are reported. The bromo-substituted species has proven to be a useful precursor in the synthesis of the cationic trimetallic system {Cp*Fe(CO)2}2(-In) + BA/4, the formation of which has been shown to be strongly dependant on the nature of abstracting agent and on the identity of the halide. Reactivity studies of {Cp*Fe(CO)2}2( i-E) + (E = Ga, In) involving the addition of nucleophiles has allowed the synthesis and characterisation of the three-coordinate cationic complexes {Cp*Fe(CO)2}2(u-E L) + BAr4 (E = Ga, In L = thf, 4-picoline, PPh3). The syntheses and metallation of sterically bulky carbazol-9-yl ligands derived from 1,8-diaryl-3,6-dimethylcarbazole are described herein. Furthermore, the synthesis and structural characterisation of the amidogally l complexes (1,8-diphenyl-3,6-dimethylcarbazol-9-yl)gallium dichloride and (1,8-dimesity 1-3,6-dimethylcarbazol-9-yl)gallium dichloride are reported by salt metathesis reactions involving gallium trichloride. Investigations of subsequent reduction chemistry using potassium metal yielded the potassium salt 1,8-diphenyl-3,6-dimethylcarbazol-9-yl-potassium. Quantum chemical investigations using Density Functional Theory have been explored to probe the electronic structure in the novel bond types. In particular, studies targeted factors affecting the degree of 7c back-bonding (and hence multiple bond character) within the TM-ER bond.

Thesis (Ph. D.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on January 30, 2008) Vita. Includes bibliographical references.

京都大学
0048
新制・課程博士
博士(工学)
甲第22155号
工博第4659号
新制||工||1727(附属図書館)
京都大学大学院工学研究科高分子化学専攻
(主査)教授 田中 一生, 教授 秋吉 一成, 教授 古賀 毅
学位規則第4条第1項該当
Doctor of Philosophy (Engineering)
Kyoto University
DGAM

This dissertation presents the synthesis and characterization of a variety of neutral and cationic complexes featuring Group 13-15 element centres stabilized by N-, P-, and O-based donors. Unique aluminum and gallium cationic complexes are obtained from equimolar reactions of the metal halide with the chelating alkyl phosphine dmpe. However, using the analogous amine donor tmeda, neutral adducts are preferred for aluminum as well as for GaCl3, while cations are obtained for GaBr3 and GaI3. New cations of Ge(II) and Sn(II) were also discovered, featuring the coordination of either bipyridine ligands or dmpe. Utilizing bipyridine led to the expected mono and dicationic chelate complexes, however, using dmpe led to the formation of unprecedented tetracationic molecules. The reactivities of the bipyridine complexes were investigated with a variety of substrates which showcased their Lewis acidity as well as their ability to be oxidized. Finally, a new series of high oxidation-state main group cations have been synthesized using a variety of ligands. The ligand choice was found to be an important role in compound isolation as ligand degradation occurred for some of the compounds due to their high electrophilicity. Additionally, the Lewis acidity of some of the complexes leads to interesting reaction chemistry including sp3 C-H activation. Overall, the results presented herein represent new coordination chemistry for the main group elements and opens the door towards new reactivity pathways including small molecule activation and catalysis.
Graduate