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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Synthesis, structural characterization and reactivity study of novel twelve-, thirteen-, and fourteen-vertex carboranes and their derivatives. / CUHK electronic theses & dissertations collection

January 2006 (has links)
By introducing a linkage between two cage carbon atoms, C,C'-linked nido-carborane salts Na2[(CH2)nC 2B10H10] (n = 5, 6) and arachno-carborane salts Li4[(CH2)nC2B10H 10] (n = 3, 4) were synthesized. The trimethylene linked carborane 1,2-(CH 2)3-1,2-C2B10H10 is a good starting material for polyhedral expansion reactions. The sequential sodium reduction followed by capitation reaction with RBX2 gave 13-vertex carboranes 3-R-1,2-(CH2)3-1,2-C2B11 H10 in moderate yields. Electrophilic substitution reactions of 1,2-(CH2)3-1,2-C2B11H 11 with suitable electrophiles gave partially substituted products 8,9,10,11,12,13-X 6-1,2-(CH2)3-1,2-C2B11H 5 (X = Me, Br, I). 13-Vertex closo-carboranes can be reduced to form 13-vertex nido-species [(CH2) 3C2B11H10R]2- by groups 1 and 2 metals. Capitation reactions of Na2[(CH2) 3C2B11H11] with dibromoborane or suitable metal halides afforded 14-vertex carborane 2,3-(CH2)3-2,3-C 2B12H12 or metallacarboranes 2,3-(CH2) 3-8-L-8,2,3-NiC2B11H11 (L = dppe, dppen) and 2,3-(CH2)3-1-(p-cymene)-1,2,3-RuC 2B11H11. Reduction of 14-vertex closo -carborane yielded 14-vertex nido-species Na 2[(CH2)3C2B12H12]. It reacted with dibromoborane to afford a new 14-vertex carborane 2,13-(CH 2)3-2,13-C2B12H12, rather than a 15-vertex one. However, a 15-vertex ruthenacarborane 1,4-(CH2 )3-7-(p-cymene)-7,1,4-RuC2B 12H12 was obtained by the capitation reaction of Na 2[(CH2)3C2B12H12] with [(p-cymene)RuCl2]2. / The reaction of Cp2ZrCl2 with Li2C 2B10H10 gave Cp2Zr(mu-Cl)(mu-C 2B10H10)Li(OEt2)2. Its reactivity toward unsaturated polar organic substrates CyN=C=NCy, PhN3, tBuNC, and PhCN resembled that of zirconocene-carboryne complex yielding a series of insertion products. The Zr-carboryne complexes (eta 5-C5Me5)(eta3-C2B 10H10)Zr(mu-Cl)2Li(THF)2, (eta 5-C5Me5)(eta3-C2B 10Me8H2)Zr(mu-Cl)2Li(OEt2) 2, and (eta5-C5Me5)Zr[eta 3-CyNC(Me)NCy](eta3-C2B10H 10) were synthesized by salt metathesis method. Among them, (eta 5-C5Me5)Zr[eta3-CyNC(Me)NCy](eta 3-C2B10H10) was active toward unsaturated polar organic substrates. Some late transition metal-carboryne complexes (PPh 3)2M(eta2-C2B10H 10) (M = Ni, Pd, Pt) were obtained from the reactions of Li2C 2B10H10 with (PPh3)2MCl 2. The ligand substitution reactions of (PPh3)2Ni(eta 2-C2B10H10) with different phosphines were studied, which revealed the labile property of the coordinated PPh 3. Different from the Zr-carboryne complexes, (PPh3) 2Ni(eta2-C2B10H10) showed regioselective [2+2+2] cycloaddition toward less bulky internal alkynes affording highly substituted benzocarboranes. / Deng Liang. / "July 2006." / Adviser: Zuowei Xie. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6393. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 152-168). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in english and Chinese. / School code: 1307.
2

Mechanism for synthesis of K* Arachno-C₂B₇H₁₂· from Arachno-4,5-C₂B₇H₁₃, and fluxional behavior of Nido-4,5-C₂B₆H₁₀

Onyema, Ezenwa Chizimako Sunny. January 2006 (has links)
Thesis (M.S.)--Villanova University, 2006. / Chemistry Dept. Includes bibliographical references.
3

Synthesis, structure and reactivity of [nido-C₂B₉H₁₁] ligands, group five and six metallacarborane complexes

Johnson, Andrew L. January 2000 (has links)
No description available.
4

Reaction of carboryne with aromatics, alkenes and ethers: preparation of functional o-carboranes.

January 2012 (has links)
鄰-碳硼炔(1,2-脫氫-鄰-碳硼烷)與烯烴、雙烯、炔烴以及芳烴可以發生[2 + 2]、[4 + 2]環加成反應和ene反應。 雖然其反應效率不高,但這些開拓性反應預示合成功能化碳硼烷化合物的全新策略,而這些結構通常由已知方法卻不能製備。此論文闡述了更為有效的碳硼炔前體(1-I-2-Li-1,2-C₂B₁₀H₁₀)的合成, 並對其兩種共振體顯著差別的反應性質進行研究,在此基礎上發展合成功能化碳硼烷化合物的有效方法。主要發生以下兩類反應:鍵合形式的碳硼炔同烷基苯、苯甲醚和苯乙烯的環加成反應;雙自由基形式的碳硼炔同脂肪族醚和二茂鐵的C-H鍵插入反應。 / 第二章闡述了鄰-碳硼炔與各種烷基取代苯的反應。反應主產物為[4 + 2]環加成反應產物,分離產率介於35%至67%之間。立體因素對產物的區域選擇性起很重要作用。在碳硼炔同甲苯的反應中,我們還分離表徵了芐基C-H鍵插入反應、串聯[4 + 2]環加成反應/homo Diels-Alder反應和串聯ene反應/[2 + 2]環加成反應形成的副產物。AgF的存在不會影響上述反應的產率和產物分佈。 / 第三章闡述了鄰-碳硼炔與苯甲醚的反應。除[4 + 2]加合物外, 反應還生成了形式環插入反應產物環辛四烯並碳硼烷。該產物由[2 + 2]環加成反應產物經熱σ-[3,3]-遷移重排而得到。立體因素對產物的區域和化學選擇性都起很重要作用,同時電子效應也可能對產物的化學選擇性有影響。上述反應形成的環辛四烯並碳硼烷和1,4-加合物分別在高溫分解和酸性條件下重新芳構化形成1-芳基-鄰-碳硼烷。 / 第四章闡述了碳硼炔與苯乙烯及其衍生物的反應。根據乙烯基上的取代基的不同情況,除預想的[2 + 2] 環加成反應與/或ene反應之外,由苯乙烯的環外雙鍵和相鄰的芳基雙鍵構成雙烯組分的環外[4 + 2]環加成反應也有發生。後者形成的中間體特別活潑以至於它們會立即經由雙自由基形式的碳硼炔的拔氫反應引發的1,3-氫遷移或者脫氫反應重新芳構化分別生成 3,4-二氫萘並[1,2]-鄰-碳硼烷和萘並[1,2]-鄰-碳硼烷。 / 第五章闡述了碳硼炔區域選擇性地插入醚基C-H鍵的反應。 在UV光照條件下,前體分子1-碘-n-鋰-1,n-碳硼烷 (n = 2, 7)很容易消除碘化鋰而生成雙自由基形式的碳硼炔。室溫下,它們經拔氫反應、單電子轉移、親核加成等系列反應後以優秀的區域選擇性插入到脂肪族醚的α-C-H鍵而形成α-碳硼烷基乙醚衍生物。該反應為合成含有烷氧基的功能化碳硼烷提供了很好方法。 / 第六章闡述了鄰-碳硼炔與二茂鐵生成二茂鐵基鄰-碳硼烷的芳基C-H鍵插入反應。我們認為,鄰-碳硼炔將二茂鐵的單電子氧化成二茂鐵陽離子對該插入反應至關重要。這一點由鋰化碳硼烷同二茂鐵(III)六氟合磷酸鹽([(η⁵-C₅H₅)2Fe]⁺[PF₆]⁻)的反應所證實。碳硼烷基自由基陰離子對二茂鐵陽離子的加合物經由自由基誘發的氫遷移或者分子內串聯的單電子轉移/質子化而得到C-H鍵插入反應產物。 / o-Carboryne (1,2-dehydro-o-carborane) is known to undergo [2 + 2], [4 + 2] cycloaddition and ene reaction with alkenes, dienes, alkynes, and aromatics. Though the efficiencies are not high, these pioneering reactions promise a new strategy for generating functionalized carboranes that are not ready to access by known methods. This thesis describes the synthesis of a more efficient precursor to carboryne, 1-I-2-Li-1,2-C₂B₁₀H₁₀, and the exploration of the significantly different reactivities of carboryne in two resonance forms, aiming at the development of efficient methodologies for functional carboranes. There are generally two classes of reactions: cycloaddition reaction of the bonding form with alkylbenzenes, anisoles, and styrenes; C-H bond insertion reaction of the biradical form with aliphatic ethers and ferrocene. / Chapter 2 describes the reaction of o-carboryne with various alkylbenzenes, which affords [4 + 2] cycloadducts as the major products in 35-67% isolated yields. Steric factors play an important role in the regioselectivity. Minor products derived from benzylic C-H bond insertion reaction, annulation reaction, tandem [4 + 2] cycloaddition/homo Diels-Alder reaction, and tandem ene reaction/[2 + 2] cycloaddition are also isolated and characterized in the reaction of carboryne with toluene. The presence of AgF in the above reaction mixture produces no notable changes in the product distributions and yields. / Chapter 3 focuses on the reaction of o-carboryne with anisoles. In addition to [4 + 2] adducts, cyclooctatetraenocarboranes, formal cycloinsertion products, are generated from the [2 + 2] cycloaddition reaction followed by thermal [3,3] sigmatropic rearrangement. Steric factors play important roles in both regio- and chemoselectivity, and electronic factors may also play a role in the chemoselectivity. Both the resulting cyclooctatetraenocarboranes and 1,4-cycloadducts from the above reactions undergo rearomatization rearrangement to give 1-aryl-o-carboranes under pyrolysis and acidic conditions, respectively. / Chapter 4 details the reaction of o-carboryne with styrene and its derivatives. In addition to the expected [2 + 2] cycloaddition reaction and/or ene reaction, an extra-annular [4 + 2] cycloaddition reaction, in which the exocyclic double bond and one of the neighboring aromatic double bonds in styrene consist of the diene component, also takes place, depending on the substituents on the vinyl unit. The resulting [4 + 2] cycloaddition intermediates are so reactive that they immediately undergo rearomatization via either a formal 1,3-hydrogen shift or dehydrogenation initiated by hydrogen abstraction with carboryne in biradical form, to give 3,4-dihydronaphtho[1,2]-o-carboranes and naphtho[1,2]-o-carboranes, respectively. / Chapter 5 presents the regioselective insertion of carborynes into the ethereal C-H bond. The biradical form of carboryne is readily generated via the elimination of LiI from 1-iodo-n-lithio-1,n-C₂B₁₀H₁₀ (n = 2, 7) under UV irradiation. They undergo α-C-H bond insertion with aliphatic ethers through a sequence of hydrogen abstraction, single-electron transfer, and nucleophilic addition, affording α-carboranylated ethers in excellent regioselectivity at room temperature. This serves as a new methodology for the generation of a series of functionalized carboranes bearing alkoxy units. / Chapter 6 addresses an aromatic C-H bond insertion reaction of o-carborynes with ferrocene to give functionalized ferrocenyl o-carboranes. It is suggested that the single-electron oxidation of ferrocene to the electrophilic ferrocenium cation by o-carborynes is crucial for the insertion reaction, which is confirmed by the reactions of lithiocarboranes with ferrocenium hexafluorophosphate. The nucleophilic adducts of the carboranyl radical anions to the ferrocenium species undergo either radical-induced hydrogen shift or tandem single electron transfer/protonation intramolecularly to give the C-H bond insertion products. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Wang, Rixin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 153-169). / Abstract also in Chinese. / Acknowledgement --- p.I / Abstract --- p.II / 摘要 --- p.IV / Abbreviation --- p.VI / List of Compounds --- p.VIII / List of Figures --- p.XIV / Contents --- p.XVII / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Skeletal Transformation --- p.3 / Chapter 1.2 --- Boron Substitution --- p.6 / Chapter 1.3 --- Carbon Substitution --- p.9 / Chapter 1.4 --- Dehydrogenation to o-Carboryne --- p.13 / Chapter 1.5 --- Our Objectives --- p.19 / Chapter Chapter 2 --- Reaction of o-Carboryne with Alkylbenzenes --- p.21 / Chapter 2.1 --- 1-I-2-Li-1,2-C₂B₁₀H₁₀: A More Efficient Carboryne Precursor --- p.21 / Chapter 2.2 --- Reaction of Carboryne with Alkylbenzenes --- p.23 / Chapter 2.3 --- Summary --- p.35 / Chapter Chapter 3 --- Reaction of o-Carboryne with Anisoles: Cycloinsertion of Carboryne into Aromatic Rings --- p.36 / Chapter 3.1 --- Dearomatization via Cycloaddition Reaction --- p.36 / Chapter 3.2 --- Reaction of Carboryne with Anisoles --- p.38 / Chapter 3.3 --- Rearrangement of Cyclooctatetraenocarboranes and Diels-Alder Adducts --- p.46 / Chapter 3.4 --- Summary --- p.52 / Chapter Chapter 4 --- Reaction of o-Carboryne with Styrenes --- p.53 / Chapter 4.1 --- Diels-Alder Reaction involving Styrenes as Dienes --- p.53 / Chapter 4.2 --- Reaction of Carboryne with Styrenes --- p.55 / Chapter 4.3 --- Summary --- p.67 / Chapter Chapter 5 --- Regioselective Insertion of Carborynes into Ethereal C-H Bonds --- p.68 / Chapter 5.1 --- Reaction of o-Carborynes with Aliphatic Ethers --- p.68 / Chapter 5.2 --- Mechanistic Studies on α-Carboranylation of Ethers --- p.74 / Chapter 5.3 --- A Revisit to Reaction of Previously Reported Carboryne Precursors with Diethyl Ether --- p.80 / Chapter 5.4 --- Summary --- p.81 / Chapter Chapter 6 --- Formal Insertion of o-Carborynes into Ferrocenyl C-H Bond --- p.82 / Chapter 6.1 --- Ferrocene --- p.82 / Chapter 6.2 --- Reaction of Carborynes with Ferrocene --- p.85 / Chapter 6.3 --- Summary --- p.95 / Chapter Chapter 7 --- Conclusion --- p.96 / Chapter Chapter 8 --- Experimental Section --- p.99 / References --- p.153 / Appendix --- p.170 / Chapter I --- Publications Based on the Research Findings --- p.170 / Chapter II --- Crystal Data and Summary of Data Collection and Refinement --- p.171 / Chapter III --- X-ray crystallographic data in CIF (electronic form) --- p.183
5

Synthesis, structural characterization and electrochemistry of 13-vertex carboranes and their radical anions.

January 2008 (has links)
Fu, Xiaodu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 93-102). / Abstracts in English and Chinese. / Acknowledgement --- p.I / Abstract (in English) --- p.II / Abstract (in Chinese) --- p.III / Abbreviation --- p.IV / List of Compounds --- p.V / List of Figures --- p.VII / Contents --- p.X / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Carboranes --- p.1 / Chapter 1.2 --- "C,C'-Linked 12-Vertex Carborane Anions" --- p.10 / Chapter 1.3 --- 13-Vertex closo-Carboranes --- p.13 / Chapter 1.4 --- 13-Vertex nido-Carborane Salts and 14-Vertex closo-Carboranes --- p.16 / Chapter 1.5 --- Carborane Radical Anions --- p.19 / Chapter 1.6 --- Our Objectives --- p.23 / Chapter Chapter 2 --- 13-Vertex Carboranes --- p.24 / Chapter 2.1 --- Synthesis and Characterization of 13-Vertex closo-Carboranes --- p.24 / Chapter 2.2 --- Molecular Structures of II-4 and II-6 --- p.30 / Chapter 2.3 --- Attempts to prepare 13-vertex carboranes with propenyl bridges --- p.33 / Chapter 2.4 --- Summary --- p.35 / Chapter Chapter 3 --- 13-Vertex Carborane Radical Anions --- p.36 / Chapter 3.1 --- Synthesis --- p.36 / Chapter 3.2 --- Structures --- p.41 / Chapter 3.3 --- Synthesis and Structure of a monoanionic salt --- p.46 / Chapter 3.4 --- Summary --- p.50 / Chapter Chapter 4 --- Electrochemical Study of 12- and 13-Vertex closo-Carboranes --- p.51 / Chapter 4.1 --- Electrochemical Study of 12-Vertex Carboranes --- p.51 / Chapter 4.2 --- Electrochemical Study of 13-Vertex Supercarboranes --- p.61 / Chapter 4.3 --- Summary --- p.74 / Chapter Chapter 5 --- Conclusion --- p.75 / Chapter Chapter 6 --- Experimental Section --- p.77 / References --- p.93 / Appendix / Chapter I. --- Publication Based on the Research Findings --- p.103 / Chapter II. --- Crystal Data and Summary of Data Collection and Refinement --- p.104 / Chapter III. --- X-ray crystallographic data in CIF (electronic form)
6

New Luminescent Materials Based on Carboranes / カルボランを基盤とした新規発光材料の創出

Kokado, Kenta 23 March 2010 (has links)
Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第15399号 / 工博第3278号 / 新制||工||1493(附属図書館) / 27877 / 京都大学大学院工学研究科高分子化学専攻 / (主査)教授 中條 善樹, 教授 伊藤 紳三郎, 教授 赤木 和夫 / 学位規則第4条第1項該当
7

Synthesis, structure, and weakly coordinating nature of new carborane anions. / CUHK electronic theses & dissertations collection

January 2000 (has links)
Chi-wing Tsang. / "July 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (p. 151-160). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
8

Synthesis, structure, and reactivity of group 4 metal-carboryne complexes. / CUHK electronic theses & dissertations collection

January 2010 (has links)
A series of group 4 metal-carboryne complexes were synthesized by the reaction of Li2C2B10H10 with dichloro group 4 metal complexes. Reaction of (eta2-C 2B10H10)ZrCl2(THF)3 with 2 equiv of [MeC(NCy)2]Li or [nPr 2NC(NPri)2]Li also effectively yielded the corresponding group-4-metal-carboryne complexes. On the other hand, treatment of C2B10H10)ZrCl2(THF) 3 with 2 equiv of tBuOK or [ tBuCOCHCOtBu]Na gave unexpected product [(eta2-C2B10H10) 2Zr(OtBu)(THF)] [Zr(OBu t)3(THF)3] or [sigma:sigma:sigma-{ tBuC(O)=CHC(tBu)(O)C 2B10H10}]Zr(eta2- tBuCOCHCOBut)(THF)2 . / Finally, the reactivities of aforementioned zirconacyclopentene and zirconacyclopentane complexes were studied. A new class of benzocarboranes and dihydrobenzocarboranes were prepared by indirect [2+2+2] cycloaddition of carboryne with two different alkynes, or with one alkene and one alkyne, mediated by Ni(II) or Fe(III). In the presence of CuCl and HMPA, zirconacyclopentenes or zirconacyclopentanes reacted with ortho-dihalobenzene reagents to generate naphthalocarborane or dihydronaphthalocarborane derivatives. A series of carborane fused cyclobutenes and cyclobutane were also prepared from zirconacyclopentenes or zirconacyclopentanes complexes mediated by Cu(II). / Next, the reactivities of Cp2Zr(mu-Cl)(mu-C2B 10H10)Li(OEt2)2 toward alkynes, alkenes and pyridines were studied. Various kinds of internal alkynes, and terminal alkenes reacted with this Zr-carboryne precursor to effectively generate the mono- insertion products zirconacyclopentene and zirconacyclopentane, respectively. Interaction of Cp2Zr(mu-Cl)(mu-C2B10H 10)Li(OEt2)2 and pyridines afforded a new kind of carboranyl zirconocene complexes via C-H activation at alpha-position of pyridines. / Subsequently, the reactivities of group 4 metal-carbroyne complexes toward unsaturated molecules were studied. Polar molecules such as azide, ketone, nitrile, carbodiimide, isocyanate, thioisocyanate, carbon disulfide, and isonitrile were inserted into the M-C bond in metal-carboryne complexes to form mono-, di-, or tri-insertion products. These metal-carboryne complexes, however, showed no reactivity toward internal alkynes and alkenes. Terminal alkynes protonated the carboryne complexes to afford neutral o-carborane. / Ren, Shikuo. / Adviser: Zuowei Xie. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 250-271). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
9

The synthesis and characterization of sterically hindered carboranylphosphine ligands

King, Arienne. Valliant, John Fitzmaurice. January 1900 (has links)
Thesis (Ph.D.)--McMaster University, 2005. / Supervisor: John F. Valliant. Includes bibliographical references.
10

The synthesis of perfluorinated compounds by direct fluorination organometallic compounds and carboranes /

Callahan, Ryan Patrick. January 2001 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references. Available also from UMI/Dissertation Abstracts International.

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