[eta5:sigma-Me2C(C5H4 )(C2B10H10]Zr[eta2-S 2C2B10H10](NHMe2)2 was prepared by amine elimination reaction between [eta5:sigma-Me 2C(C5H4)(C2B10H10)]Zr[NMe 2)2 and 1,2-(HS)2-1,2-C2B10 H10. It underwent ligand substitution reaction with XylNC to generate [eta5:sigma-Me2C(C5H 4)(C2B10H10]Zr[eta2-S 2C2B10H10][2,6-(CH3) 2C6H3N=C]2 and reacted with THE to give ring opening product [eta5:sigma-Me2C(C 5H4)(C2B10H10]ZR-[eta 2-S2C2B10H10][sigma-O(CH 2)4NHMe2)]. Zirconium-promoted nucleophilic reaction of dimethylamine with various kinds of unsaturated polar organic substrates, such as PhCN, PhNCO, nBuNCS and MA were studied. / Direct deboration of group 4 metal carboranyl complexes was achieved by reactions of [eta5:sigma-Me2C(C5H 4)(C2B10H10]M[NMe2) 2 (M = Zr, Hf), [eta5:sigma-Me2C(C 9H6)(C2B10H10]Zr[NMe 2)2 or [eta5:sigma-H2C(C 13H8)(C2B10H10]Zr[NMe 2)2 with excess diamines. The resultant metal dicarbollide complexes [eta5:eta6-Me2C(C 5H4)(C2B9H10)]Zr[eta 2-N(Me)(Ch2)2NH(Me)] and [eta5:eta 6-Me2C(C5H4)(C2B 9H10]Zr[eta2-[NMe)(CH2) 3NH(Me)] were active toward unsaturated molecules, like nBuNCS, iPr-N=C=N- iPr and nBuNC, to give mono-insertion products. [eta5:eta6-Me2C(C 5H4)(C2B9H10)]Zr[eta 2-N(Me)(CH2)3NH(Me)] was able to be deprotonated by nBuLi to give a lithium salt {[eta 5:eta-6-Me2C(C5H4)(C 2B9H10)]Zr[eta2-N(Me)(CH 2)3N(Me)Li]}2. It reacted with [HNEt3][BPh 4] to afford cationic zirconium species [eta5:eta 6-Me2C(C5H4)(C2B 9H10]Zr{eta2-NH(Me)(CH2) 3NH(ME)}][BPh4]. The dichloro species [eta5:eta 6-Me2C(C5H4)(C2B 9H10}MCl2][Li(DME)3)] (M = Zr, Hf) were reduced by sodium metal to produce a new class of metallacarbornes bearing arachno-eta6-C2B9 tetraanion. / The amine exchange reaction between [eta5:sigma-Me 2C(C5H4)(C2B10H10]M[NMe 2)2 (M = Zr, Hf, Ti) and N, N'-dimethylethylenediamine or N, N'-dimethylpropane-1,3-diamine gave [eta5:sigma-Me 2C(C5H4)(C2B10H10]M-[eta 2N(Me)(CH2)2N(Me)] (M = Zr, Ti) or [eta 5:sigma-Me2C(C5H4)(C2B 10H10]M-[eta2N(Me)(CH2) 3N(Me)] (M= Zr, Hf, Ti) in good yields. The metal-nitrogen bonds in these group 4 metal diamide complexes were very reactive toward unsaturated polar organic substrates, such as RNC, RNCS, RNCO, R-N=C=N-R and RCN to give multiple insertion products. The carbodiimide and XylNC (Xyl = 2,6-Me 2C6H3) insertion products [eta5:sigma-Me 2C(C5H4)(C2B10H10]M-[eta 3N(Me)(CH2)3N(Me)C(=NR)NR] (M = Zr, R = iPr, Cy; M = Hf, R = Cy) and [eta5:sigma-Me 2C(C5H4)(C2B10H10]M-[eta 2:eta2-N(Xyl)=CN(Me)(CH2)3N(Me)C=N(Xyl)] (M = Zr, Hf) also showed reactivities toward unsaturated molecules, resulting in the de-insertion of carbodiimide and XylNC. Different reactivity patterns were observed, depending on the nature of metal atoms and substrates. / Sit, Mei Mei. / Adviser: Zuowei Xia. / Includes supplementary digital materials. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 247-267). / 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, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
| Identifer | oai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_344724 |
| Date | January 2010 |
| Contributors | Sit, Mei Mei., Chinese University of Hong Kong Graduate School. Division of Chemistry. |
| Source Sets | The Chinese University of Hong Kong |
| Language | English, Chinese |
| Detected Language | English |
| Type | Text, theses |
| Format | electronic resource, microform, microfiche, 1 online resource (xxiii, 285 leaves : ill.) |
| Rights | Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/) |
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