Thesis (Ph. D.)--Rutgers University, 2010. / "Graduate Program in Chemistry." Includes bibliographical references.

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 185-191). Also available via the Internet.

Luminescent transition metal complexes have arisen as viable alternatives to organic dyes for sensory applications due to their notable advantages. This thesis aimed to synthesize different kinds of Ir(III) complexes, explore their interactions with DNAs and investigate their application for the construction of label-free oligonucleotide-based sensing platforms. A series of Ir(III) complexes incorporating a variety of C^N and N^N donor ligands were synthesized and were shown to exhibit G-quadruplex-selective binding properties via emission titration, UV/vis titration, fluorescence resonance energy transfer melting and G-quadruplex fluorescent intercalator displacement experiments. These G-quadruplex-selective Ir(III) complexes were utilized as signal transducers to monitor the conformational changes of oligonucleotides in label-free oligonucleotide-based luminescent detection platforms for metal ion (Sr2+), small molecules (GSH and ATP), protein (human neutrophil elastase) and enzyme activities (polymerase, hepatitis C virus NS3 helicase).

Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references. Also available in electronic version.

The oxidative addition of the N-H bond of both heterocyclic and acyclic amines and the O-H bond of phenols, water and carboxylic acids to iridium(I) trimethylphosphines complexes was studied and the reactivity of the resulting hydrido amido-, aryloxo- and carboxylato iridium(III) complexes was investigated. Oxidative addition of the N-H bond of pyrrole, indole, 3-methylindole, 7-azaindole, carbazole and aniline to [Ir(COD)(PMe₃)₃]CI (<b>1a</b>) (COD = 1,5-cyclooctadiene) produces merIr( NR₂)H(PMe₃)₃CI (<b>2a-f</b>) complexes. That these amines were bound to iridium through an Ir-N bond was established by ¹H, ³¹P and ¹³C NMR spectroscopy, IR spectroscopy, C-H analyses and single crystal x-ray diffraction. Similarly, oxidative addition of the O-H bond of phenol, p-cresol, 3,5-dimethylphenol, and water to [Ir(COD)(PMe₃)₃]CI (la) produces mer-Ir(OR)H(PMe₃)₃C1 (<b>5a-c and 6</b>) which were characterized by ¹H, ³¹P and ¹³C NMR spectroscopy, C H analyses and single crystal x-ray diffraction. A preliminary study of the reactivity of both the amido and aryloxo complexes suggests that because of the increased electron affinity of the heteroatoms involved (N or 0), there is high electron density at the heteroatoms in these complexes and therefore the M-N or M-O bond can heterolyze more easily than M-C bonds. This increased tendency of the M-N or M-O bond to heterolyze leads to decomposition reactions when attempts are made to open up a coordination site at the metal center by removing the chloride ligand. / Ph. D.

Thesis (Ph. D.)--Rutgers University, 2007. / "Graduate Program in Chemistry and Chemical Biology." Includes bibliographical references.

The oxidative addition of H-H to iridium(l) trimethylphosphine complexes was studied and the reactivity of the resulting water soluble dihydrido iridium (III) complexes was investigated. One Dihydrido iridium(III) complex, mer-Ir(H)₂(PMe₃)₃CI <b>(2)</b> was characterized by ¹H, ³¹p and ¹³C NMR spectroscopy, CH analysis and single crystal xray diffraction. <b>(2)</b> reacted with the strong sigma donor PMe₃ to form [IrH2(PMe₃)4]CI <b>(3b)</b> without having to remove the chloride ligand. <b>(2)</b> reacted with monosubstituted acetylenes and an internal diyne in water to form the vinyl complexes Ir(H)(C(R')=C(H)-(R))(PMe₃)₃CI (R = CMe₃, C₆H₅, SiMe₃, R' = H, <b>(4)-(6);</b> R' = CCMe₃, R= Me, <b>(7)). (2)</b> also reacted in water with ethynylpyridine to form an unusual metallacycle "trimer" <b>(8)</b>. A mechanism for tltrimerizationtl is proposed. <b>(2)</b> also reacted with ethylene in water to form the diethyl iridium complex Ir(CH₂CH₃)₂(PMe₃)₃CI <b>(8)</b>. Encouraged by these results, catalytic hydrogenation of unsaturates in water was investigated. It was found that <b>(2)</b> is active as a water soluble catalyst for hydrogenation of unsaturates. A mechanism for catalytic hydrogenation was proposed. / Ph. D.

This thesis describes the catalysed addition of X-H bonds (X = S, O and N) to alkynes using a range of novel rhodium(I) and iridium(I) complexes containing hybrid bidentate phosphine-pyrazolyl, phosphine-imidazolyl and phosphine-N heterocyclic carbene (NHC) donor ligands. The synthesis of novel bidentate phosphine-pyrazolyl, phosphine-imidazolyl (P-N) and phosphine-NHC (PC) donor ligands and their cationic and neutral rhodium(I) and iridium(I) complexes [M(P N)(COD)]BPh4, [M(PC)(COD)]BPh4, [Ir(P-N)(CO)2]BPh4 and [M(P-N)(CO)Cl] were successfully performed. An unusual five coordinate iridium complex with phosphine-NHC ligands [Ir(PC)(COD)(CO)]BPh4 was also obtained. Seventeen single crystal X-ray structures of these new complexes were determined. A range of these novel rhodium and iridium complexes were effective as catalysts for the addition of thiophenol to a variety of alkynes. Iridium complexes were more effective than rhodium analogues. Cationic complexes were more effective than neutral complexes. Complexes with hybrid phosphine-nitrogen donor were more effective than complexes containing bidentate nitrogen donor ligands. An atom-economical, efficient method for the synthesis of cyclic acetals and bicyclic O,O-acetals was successfully developed based on the catalysed hydroalkoxylation. Readily prepared terminal and non-terminal alkyne diols were cyclised into bicyclic O,O-acetals in quantitative conversions in most cases. The efficiency of a range of rhodium and iridium complexes containing bidentate P-N and PC donor ligands as catalysts for the cyclisation of 4-pentyn-1-amine to 2-methyl-1-pyrroline varied significantly. The cationic iridium complexes with the bidentate phosphine-pyrazolyl ligands, [Ir(R2PyP)(COD)]BPh4 (2.39-2.42) were extremely efficient as catalysts for this transformation. Increasing the size of the substituent on or adjacent to the donor led to improvement in catalytic activity of the corresponding metal complexes. The mechanism of the catalysed hydroalkoxylation was proposed to proceed by the initial activation of the alkyne via ?? coordination to the metal centre. The ?? binding of both aliphatic and aromatic alkynes to [Ir(PyP)(CO)2]BPh4 (2.44) was observed by low temperature NMR and no reaction between 2.44 and alcohols was observed. In contrast, the facility in which thiol and amine oxidatively added to 2.44 led the proposal that in the hydrothiolation and hydroamination reaction, the catalytic cycle commences with the activation of the X-H bond (X = S, N) by an oxidative addition process.

This thesis describes the catalysed addition of X-H bonds (X = S, O and N) to alkynes using a range of novel rhodium(I) and iridium(I) complexes containing hybrid bidentate phosphine-pyrazolyl, phosphine-imidazolyl and phosphine-N heterocyclic carbene (NHC) donor ligands. The synthesis of novel bidentate phosphine-pyrazolyl, phosphine-imidazolyl (P-N) and phosphine-NHC (PC) donor ligands and their cationic and neutral rhodium(I) and iridium(I) complexes [M(P N)(COD)]BPh4, [M(PC)(COD)]BPh4, [Ir(P-N)(CO)2]BPh4 and [M(P-N)(CO)Cl] were successfully performed. An unusual five coordinate iridium complex with phosphine-NHC ligands [Ir(PC)(COD)(CO)]BPh4 was also obtained. Seventeen single crystal X-ray structures of these new complexes were determined. A range of these novel rhodium and iridium complexes were effective as catalysts for the addition of thiophenol to a variety of alkynes. Iridium complexes were more effective than rhodium analogues. Cationic complexes were more effective than neutral complexes. Complexes with hybrid phosphine-nitrogen donor were more effective than complexes containing bidentate nitrogen donor ligands. An atom-economical, efficient method for the synthesis of cyclic acetals and bicyclic O,O-acetals was successfully developed based on the catalysed hydroalkoxylation. Readily prepared terminal and non-terminal alkyne diols were cyclised into bicyclic O,O-acetals in quantitative conversions in most cases. The efficiency of a range of rhodium and iridium complexes containing bidentate P-N and PC donor ligands as catalysts for the cyclisation of 4-pentyn-1-amine to 2-methyl-1-pyrroline varied significantly. The cationic iridium complexes with the bidentate phosphine-pyrazolyl ligands, [Ir(R2PyP)(COD)]BPh4 (2.39-2.42) were extremely efficient as catalysts for this transformation. Increasing the size of the substituent on or adjacent to the donor led to improvement in catalytic activity of the corresponding metal complexes. The mechanism of the catalysed hydroalkoxylation was proposed to proceed by the initial activation of the alkyne via ?? coordination to the metal centre. The ?? binding of both aliphatic and aromatic alkynes to [Ir(PyP)(CO)2]BPh4 (2.44) was observed by low temperature NMR and no reaction between 2.44 and alcohols was observed. In contrast, the facility in which thiol and amine oxidatively added to 2.44 led the proposal that in the hydrothiolation and hydroamination reaction, the catalytic cycle commences with the activation of the X-H bond (X = S, N) by an oxidative addition process.