PART 1: FORMATION OF SOME HETEROCYCLIC COMPOUNDS CONTAINING BORON, CARBON, NITROGEN, AND AN ELEMENT OF GROUP VI. PART 2: MECHANISM OF POLYMERIZATION OF IMIDAZOLE BORANE.

Persistent Link:
http://hdl.handle.net/10150/186757
Title:
PART 1: FORMATION OF SOME HETEROCYCLIC COMPOUNDS CONTAINING BORON, CARBON, NITROGEN, AND AN ELEMENT OF GROUP VI. PART 2: MECHANISM OF POLYMERIZATION OF IMIDAZOLE BORANE.
Author:
KNAPP, KRAIG KENT.
Issue Date:
1983
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Part I: Compounds of the type benzo(group VI)azole (I) were treated with diborane using standard vacuum line techniques. The group VI elements were oxygen. sulfur. and selenium. Initially. an insoluble borane adduct formed which spontaneously reduced and replaced carbon in the hetero-ring by boron via an unstable intermediate either (II) or (III). For example. benzoxazole reacted to produce 2-H-3-methyl-l.3.2- benzoxazaborole (IV). The 2-H-3-alkyl-l,3.2-benzo(group VI)azaboroles (V) were easily purified. produced in high yield, and upon methanolysis yielded N-alkyl-2-(group VI)anilines (VI). These boroles were characterized by IR, H-l and B-ll NMR spectra, and mass spectroscopy. Part II: Kinetics of the polymerization of imidazole-borane in the presence of diborane was followed by monitoring hydrogen production at 30°C. Pseudo first-order kinetics was observed at all ratios of diborane to irnidazole-borane, and the observed rate constant increased linearly with excess diborane. A mechanism is proposed in which the diborane acts as a catalyst. Half the hydrogen molecule comes from the diborane, while the other half comes from the nitrogen-bonded hydrogen on imidazole-borane. Hydrogen is formed when diborane reacts with imidazole-borane in a slow step. followed by fast coupling with another imidazole-borane and regeneration of diborane. The structure of the polymer is shown below (VII). and the average size of the polyme1 was 32-38 units.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Organoboron compounds -- Spectra.; Organoboron polymers.; Polymers.; Polymerization.; Imidazoles.; Boranes.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Chemistry; Graduate College
Degree Grantor:
University of Arizona
Advisor:
Rund, John

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titlePART 1: FORMATION OF SOME HETEROCYCLIC COMPOUNDS CONTAINING BORON, CARBON, NITROGEN, AND AN ELEMENT OF GROUP VI. PART 2: MECHANISM OF POLYMERIZATION OF IMIDAZOLE BORANE.en_US
dc.creatorKNAPP, KRAIG KENT.en_US
dc.contributor.authorKNAPP, KRAIG KENT.en_US
dc.date.issued1983en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractPart I: Compounds of the type benzo(group VI)azole (I) were treated with diborane using standard vacuum line techniques. The group VI elements were oxygen. sulfur. and selenium. Initially. an insoluble borane adduct formed which spontaneously reduced and replaced carbon in the hetero-ring by boron via an unstable intermediate either (II) or (III). For example. benzoxazole reacted to produce 2-H-3-methyl-l.3.2- benzoxazaborole (IV). The 2-H-3-alkyl-l,3.2-benzo(group VI)azaboroles (V) were easily purified. produced in high yield, and upon methanolysis yielded N-alkyl-2-(group VI)anilines (VI). These boroles were characterized by IR, H-l and B-ll NMR spectra, and mass spectroscopy. Part II: Kinetics of the polymerization of imidazole-borane in the presence of diborane was followed by monitoring hydrogen production at 30°C. Pseudo first-order kinetics was observed at all ratios of diborane to irnidazole-borane, and the observed rate constant increased linearly with excess diborane. A mechanism is proposed in which the diborane acts as a catalyst. Half the hydrogen molecule comes from the diborane, while the other half comes from the nitrogen-bonded hydrogen on imidazole-borane. Hydrogen is formed when diborane reacts with imidazole-borane in a slow step. followed by fast coupling with another imidazole-borane and regeneration of diborane. The structure of the polymer is shown below (VII). and the average size of the polyme1 was 32-38 units.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectOrganoboron compounds -- Spectra.en_US
dc.subjectOrganoboron polymers.en_US
dc.subjectPolymers.en_US
dc.subjectPolymerization.en_US
dc.subjectImidazoles.en_US
dc.subjectBoranes.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineChemistryen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.advisorRund, Johnen_US
dc.identifier.proquest8322645en_US
dc.identifier.oclc690021087en_US
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