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dc.contributor.advisorMiller, Stephen A
dc.creatorReich, Blair Jesse Ellyn
dc.date.accessioned2007-04-25T20:15:19Z
dc.date.available2007-04-25T20:15:19Z
dc.date.created2005-12
dc.date.issued2007-04-25
dc.identifier.urihttps://hdl.handle.net/1969.1/4987
dc.description.abstractCyanide-catalyzed aldimine coupling was employed to synthesize compounds with 1,2-ene-diamine and α-imine-amine structural motifs: 1,2,N,N'- tetraphenyletheylene-1,2-diamine (13) and (+/-)-2,3-di-(2-hydroxyphenyl)-1,2- dihydroquinoxaline (17), respectively. Single crystal X-ray diffraction provided solidstate structures and density functional theory calculations were used to probe isomeric preferences within this and the related hydroxy-ketone/ene-diol system. The enediamine and imine-amine core structures were calculated to be essentially identical in energy. However, additional effects-such as π conjugation-in 13 render an enediamine structure that is slightly more stable than the imine-amine tautomer (14). In contrast, the intramolecular hydrogen bonding present in 17 significantly favors the imine-amine isomer over the ene-diamine tautomer (18). Aldimine coupling (AIC) is the nitrogen analogue of the benzoin condensation and has been applied to dialdimines, providing the first examples of cyclizations effected by cyanide-catalyzed AIC. Sodium cyanide promoted the facile, intramolecular cyclization of several dialdimines in N,N-dimethylformamide, methanol, or dichloromethane/water (phase-transfer conditions) yielding a variety of six-membered heterocycles. Under aerobic conditions, an oxidative cyclization occurs to provide the diimine heterocycle. Cyanide-catalyzed aldimine coupling was employed as a new synthetic method for oligomerization. Nine rigidly spaced dialdimines were oxidatively coupled under aerobic conditions to yield conjugated oligoketimines and polyketimines with unprecedented structure and molecular weight (DP = 2 - 23, ~700 -8200 g/mol). The α- diimine linkage was established based on IR spectroscopy, NMR spectroscopy, size exclusion chromatography, and X-ray crystallographic characterization of the model oxidized dimer of N-benzylidene-(p-phenoxy)-aniline. Cyclic voltammetry indicates ptype electrical conductivity, suggesting they are promising candidates for plastic electronic devices. The cyanide-catalyzed benzoin condensation reaction of 4-substituted benzaldehydes followed by oxidation to the diketone, and the Schiff Base condensation of two equivalents of o-aminophenol provides 2,3-(4-X-phenyl)2-1,4-(2- hydroxyphenyl)2-1,4-diazabutadiene. The ligand is given the moniker X-dabphol. These ligands are readily metallated to form M-X-dabphol complexes. The copper complexes catalytically fix CO2 with propylene oxide to yield propylene carbonate. DFT studies along with a comparison with Hammet parameters help validate and elaborate on the catalytic cycle and the catalytic results obtained. The nickel complex is competent for olefin epoxidation. Synthesis, characterization, X-ray structure, DFT analysis, and catalytic activity of the parent nickel dabphol complex are reported.en
dc.format.extent5471568 bytesen
dc.format.mediumelectronicen
dc.format.mimetypeapplication/pdf
dc.language.isoen_US
dc.publisherTexas A&M University
dc.subjectAICen
dc.subjectbenzoin condensationen
dc.subjectaldimineen
dc.subjectene-diamineen
dc.subjectimine-amineen
dc.subjectcyclic proponateen
dc.subjectpropylene carbonateen
dc.subjectdabpholen
dc.subjectepoxidationen
dc.titleCyanide-catalyzed C-C bond formation: synthesis of novel compounds, materials and ligands for homogeneous catalysisen
dc.typeBooken
dc.typeThesisen
thesis.degree.departmentChemistryen
thesis.degree.disciplineChemistryen
thesis.degree.grantorTexas A&M Universityen
thesis.degree.nameDoctor of Philosophyen
thesis.degree.levelDoctoralen
dc.contributor.committeeMemberDarensbourg, Marcetta
dc.contributor.committeeMemberGabbai, Francois P
dc.contributor.committeeMemberShantz, Daniel F
dc.type.genreElectronic Dissertationen
dc.type.materialtexten
dc.format.digitalOriginborn digitalen


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