Graduate Thesis Or Dissertation

 

Low temperature thermal analysis of some boron halide complexes with weak Lewis bases Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/xp68kk463

Descriptions

Attribute NameValues
Creator
Abstract
  • Thermal analysis was used to investigate the following seven systems: H₂S-B₂F₄, SOF₂-B₂F₄, COC1₂-B₂F₄, SF₄-B₂F₄, Xe-BF₃, NF₃-BF₃, and NF₃-BC1₃. In two of the seven systems compound formation was observed. In the system, H₂S-B₂F₄ the compounds H₂S[superscript .]B₂F₄ and 2H₂S[superscript .]B₂F₄ are formed. The compound H₂S[superscript .]B₂F₄ has a melting point of -94.99 ± 0.3° C while the compound 2H₂S[superscript .]B₂F₄ melts at -100.3 ± 0.3° C. The system has three eutectics at 16.2, 35.2 and 50.5 mole percent B₂F₄ and at -107.4 ± 0.3° C, -100.4 ± 0.3° C, and -94.9 ± 0.3° C, respectively. In the system, SF₄-B₂F₄ the compound SF₄[superscript .]B₂F₄ is formed. The SF₄[superscript .]B₂F₄ slowly decomposes at room temperature. Two eutectics are found in the phase diagram at 3 ± 2 and 98 ± 2 mole percent B₂F₄ and at -116.3 ± 0.5° C and -59.8 ± 0.5° C, respectively. The system, SOF₂-B₂F₄ has a single eutectic at 24 mole percent B₂F₄ and a temperature of -141.7 ± 0.5° C. The two components are completely miscible. The system, COC1₂-B₂F₄ has a single eutectic at four mole percent B₂F₄ and a temperature of -132.5 ± 0.5° C. The two components are completely miscible. The compounds Xe and BF₃ are immiscible although BF₃ is slightly soluble in liquid Xe. Xe is completely insoluble in liquid BF₃. The compounds NF₃ and BF₃ are immiscible although NF₃ is slightly soluble in liquid BF₃. The solubility of BF₃ in liquid NF₃ was not investigated. The compounds NF₃ and BC1₃ are immiscible with NF₃ being very slightly soluble in liquid BC1₃. The solubility of BC1₃ in liquid NF₃ was not investigated. BF₃ is shown to displace B₂F₄ from the complex SF₄[superscript .]B₂F₄ in 93% yield. BF₃ is a stronger Lewis acid than either BC1₃ or B₂F₄ toward the Lewis bases SOF₂ and COC1₂ on the basis of compound formation. No conclusion can be drawn about the relative acid strengths of BC1₃ and B₂F₄ relative to these two bases. Based on acid displacement, BF₃ is a stronger Lewis acid than B₂F₄ relative to the Lewis base SF₄. Toward the Lewis base H₂S, the order of increasing Lewis acidity appears to be B₂F₄ < BF₃ < BC1₃, B₂C1₄. This is a qualitative order based on the height of the maximum between eutectics in the phase diagrams. Some difficulty was encountered with the synthesis of B₂F₄. Possible reasons for these difficulties are discussed. The generally weaker acidity of B₂F₄ as compared to BF₃ is accounted for on the basis of electronegativity and steric considerations.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi using Capture Perfect 3.0 on a Canon DR-9050C in PDF format. CVista PdfCompressor 5.0 was used for pdf compression and textual OCR.
Replaces
Additional Information
  • description.provenance : Submitted by Madison Medley (mmscannerosu@gmail.com) on 2014-04-18T22:04:38Z No. of bitstreams: 1 LerchRonaldE1966.pdf: 741523 bytes, checksum: bfc5596c03a463bcebc5ca574725aa3e (MD5)
  • description.provenance : Approved for entry into archive by Patricia Black(patricia.black@oregonstate.edu) on 2014-04-21T14:12:38Z (GMT) No. of bitstreams: 1 LerchRonaldE1966.pdf: 741523 bytes, checksum: bfc5596c03a463bcebc5ca574725aa3e (MD5)
  • description.provenance : Approved for entry into archive by Katy Davis(kdscannerosu@gmail.com) on 2014-04-21T17:49:34Z (GMT) No. of bitstreams: 1 LerchRonaldE1966.pdf: 741523 bytes, checksum: bfc5596c03a463bcebc5ca574725aa3e (MD5)
  • description.provenance : Made available in DSpace on 2014-04-21T17:49:34Z (GMT). No. of bitstreams: 1 LerchRonaldE1966.pdf: 741523 bytes, checksum: bfc5596c03a463bcebc5ca574725aa3e (MD5) Previous issue date: 1966-04-25

Relationships

Parents:

This work has no parents.

In Collection:

Items