Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemistry, 2015. / Cataloged from PDF version of thesis. Vita. Page 216 blank. / Includes bibliographical references. / Complexes (THF)₀-₂E[P₃Nb(ODipp)₃]₂ (E = Sn, Pb; Dipp = 2,6-iPr₂C₆H₃) were prepared and characterized as potential precursors to new tetrel phosphides. Treatment of (THF)Sn[P₃Nb(ODipp)₃]₂ with pyridine-N-oxide effected the formation of ONb(ODipp)₂(py)₂ and a new tin phosphide, [(THF)SnP₆]x, characterized using a multitude of techniques. Additionally, P₃Nb(ODipp)₂(py)₂, prepared from [Na(THF)₃][[P₃Nb(ODipp)₃] in the presence of pyridine and salts of coordinating cations, was found to successfully produce AsP₃ upon treatment with AsCl₃ Dimer [P₂Nb(ODipp)₃]₂ has been obtained via a novel "2(3-1)" synthetic strategy. The mononuclear diphosphorus complex P₂Nb(ODipp)₃ proposed to be generated transiently by formal P- abstraction from previously reported [Na(THF)₃][P₃Nb(ODipp)₃] undergoes irreversible dimerization to form the [P₂Nb(ODipp)₃]₂ complex, and is alternatively trapped reversibly by a 1,3-cyclohexadiene (CHD) to form in situ C₆H₈P₂Nb(ODipp)₃ Unprotected dibenzo-7[lambda]³A3-phosphanorbornadiene derivatives RPA (A= C₁₄H₁₀ or anthracene; R = tBu, dbabh, HMDS, iPr₂N, cis-Me₂ Pip, Cy₂N, Me₂N) were synthesized by treatment of the corresponding phosphorus dichloride RPCl₂ with MgA-3THF. Thermolysis of RPA benzene-d₆ solutions leads to anthracene extrusion. Experimental and computational thermodynamic activation parameters suggest this process occurs through the intermediacy of a singlet phosphinidene for the iPr₂N derivative. The [RP] unit could be transferred to CHD, a carbene and an ortho-benzoquinone, with formation of the corresponding anti-7-phosphanorbornene, phosphaalkene and phospholane. The anthracene diphosphorus adduct P₂A₂ was synthesized from Me₂NPA, through isolated intermediates CIPA and [P₂A₂Cl][AlCl₄]. P₂A₂ was found to transfer P₂ efficiently to N-₃ CHD, 1,3-butadiene and (C₂H₄)Pt(PPh₃)₂ to form 1,2-cyclo-[P₂N₃]-, P₂(CHD)₂, P₂(BD)₂ and (P₂)[Pt(PPh₃)₂]₂ . A complete kinetic and computational study of the P₂(CHD)₂ formation from P₂A₂ suggests P₂ is a productive intermediate in solution. Additionally, a molecular beam mass spectrometry study on the thermolysis of solid P₂A₂ reveals the direct detection of molecular fragments of only P₂ and anthracene thus establishing a link between solution-phase P₂-transfer chemistry and production of gas-phase P₂ by mild thermal activation of a molecular precursor. The HCP precursor Ph₃PC(H)PA was synthesized directly from C1PA. The activation of P₄ with [Na][SnPh₃ ] and sodium naphthalenide led to the synthesis of phosphide compounds [Na(benzo-15-crown-5)][P(SnPh₃)₂], P(SnPh₃)₃, (XL)₂InP(SnPh₃)₂, (Ph₃P)AuP(SnPh₃)₂, P₇(SnPh₃)₃ and P7(SiMe₃)₃, characterized using a variety of techniques. / by Alexandra Velian. / Ph. D.
| Identifer | oai:union.ndltd.org:MIT/oai:dspace.mit.edu:1721.1/97986 |
| Date | January 2015 |
| Creators | Velian, Alexandra |
| Contributors | Christopher C. Cummins., Massachusetts Institute of Technology. Department of Chemistry., Massachusetts Institute of Technology. Department of Chemistry. |
| Publisher | Massachusetts Institute of Technology |
| Source Sets | M.I.T. Theses and Dissertation |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | xxviii, 216 pages, application/pdf |
| Rights | M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission., http://dspace.mit.edu/handle/1721.1/7582 |
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