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dc.contributor.authorDunlop-Brière, Alexandreen
dc.date2014-12-19 18:16:32.168
dc.date2014-12-23 12:42:02.115
dc.date.accessioned2014-12-23T19:56:07Z
dc.date.available2014-12-23T19:56:07Z
dc.date.issued2014-12-23
dc.identifier.urihttp://hdl.handle.net/1974/12672
dc.descriptionThesis (Ph.D, Chemistry) -- Queen's University, 2014-12-23 12:42:02.115en
dc.description.abstractIn chapter 2, the synthesis and NMR characterization of [Cp2TiCH3(H2O)]+ (I) is presented. In the presence of excess water, there is evidence of rapid H-exchange and H-bonding between coordinated and free water. At higher temperatures, I undergoes hydrolysis to produce methane. In chapter 3, formation of [Cp2TiCH2CHMeCMe3]+ (II) via a controlled single 1,2-migratory insertion reaction of [Cp2TiMe]+ and 3,3-dimethyl-1-butene (3,3-DMB) at 205 K is presented. II exchanges between its two α-agostic isomers, with a preference for one agostic isomer over the other and also remains α-agostic under coordination of Et2O. In chapter 4, [Cp2TiCH2CHMeSiMe3]+ (III), a complex that is exchanging between γ- (ground state) and β- agostic isomers, is prepared by reaction of [Cp2TiMe]+ with 1 equivalent of trimethylvinylsilane at 205 K. There is exchange between β-H and γ-H from 215 K to 260 K but 1H NMR data suggests no or very little increase in rate. [Cp2TiCH2CHCD3SiMe3]+ undergoes a reversible and exclusive isotopomeric rearrangement to form specifically [Cp2TiCD2CDCH3SiMe3]+ through a series of reversible β-H elimination, 2,1- and 1,2- migratory-insertion reactions (process 1). Deuteration of III at β- or γ- positions essentially shuts down the β-H/γ-H exchange, with a kH/kD of at least 13000 at 225 K. These results indicate that this latter exchange process is driven by H quantum mechanical tunneling (QMT). Finally, chapter 5 presents is a re-investigation of II that unravels some exchange processes that were not detected in previous studies of II. EXSY and D-labeling (of β-Me in II) experiments suggest that II also undergoes process 1. Olefin dissociation from [Cp2TiH(CH2=CMeCMe3)]+ is faster than process 1 and EXSY correlations are seen intermolecularly between II and 2,3,3-TMB, as well as intramolecularly in 2,3,3-TMB (fastest exchange). In II-d3, this rapid reversible olefin dissociation from the olefin-hydride complex coupled to process 1 leads to multiple isotopologuous rearrangements in 2,3,3-TMB before it can be re-incorporated in II, with similar overall rates of deuterium incorporation at all α- and β- sites in II-dx (x = 0-6, statistical distribution with an average value of 3).en
dc.language.isoengen
dc.relation.ispartofseriesCanadian thesesen
dc.rightsThis publication is made available by the authority of the copyright owner solely for the purpose of private study and research and may not be copied or reproduced except as permitted by the copyright laws without written authority from the copyright owner.en
dc.subjecttitanoceneen
dc.subjectolefin polymerizationen
dc.subjectalpha-agosticen
dc.subjectagosticen
dc.subjectbeta-agosticen
dc.subjectgamma-agosticen
dc.subjectH-tunnellingen
dc.subjectintermediateen
dc.titleSTRUCTURE AND PROPERTIES OF SOME α-, β- AND γ-AGOSTIC ALKYL-TITANOCENE COMPLEXESen
dc.typethesisen
dc.description.degreePhDen
dc.contributor.supervisorBaird, Michael C.en
dc.contributor.departmentChemistryen
dc.degree.grantorQueen's University at Kingstonen


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