烯烴是世界上最被廣泛應用的化工原料之一。最近我們通過含氮雜環卡賓鎳氫化物來催化氫化烯化反應，用廉價的單取代簡單烯烴成功合成了更有價值的不對稱1，1-偕二取代烯烴。雖然它們的對映體可以由傳統的手性拆分方法在實驗室中獲得，但卻不太可能實際應用於工業中，從而限制了此新方法的可應用性。因此，本文中我們透過使用烯烴醛耦合反應生成手性含氮雜環卡賓鎳氫化物 [(NHC)NiH]OTf，並以此為催化劑，將其應用在溫和條件下高選擇性的催化不對稱氫化烯化反應。另外，上述烯烴醛耦合反應的副產物 (烯丙基矽醚) 亦可成為基板，通過催化受控的替換反應，最後合成並得出較高取代的烯烴。基於烯丙基磷酸二芳酯為目前在生物學上中一種重要的研究項目，以及其當前製備的困難，我們通過形成碳磷鍵來探索這些烯丙基矽醚的可應用性。故此，在現有的磷碳反應文獻和 Ritter 反應的鼓舞下，我們提供開發烯丙基磷酸二芳酯在溫和條件下的催化製備方法。此方法除可補充現有製備方法的不足外，亦能增加此類化合物有較高的取代基靈活性。 / Alkenes are one of the most versatile chemical feedstock in chemistry. Among the numerous preparative strategies, hydroalkenylation (H.A.) by using N-heterocyclic carbene (NHC)-NiH reported recently by our group represents a novel strategy to access synthetically valuable unsymmetric terminal 1, 1-disubstituted alkenes (DSA) from widely available α-alkenes. Their enantiomers could be obtained by classic chiral resolution methods in laboratory but may not be practical in industry, which limits the applications of this new methodology. As a result, herein we developed a catalytic asymmetric H.A. with high selectivities under mild conditions based on a chiral [(NHC)NiH]OTf catalyst generated in situ from alkene-aldehyde (A.A.) coupling. Since the above A.A. coupling by-product (allyl silyl ethers) is a structural motif potentially amenable for higher alkene catalytic synthesis by a controlled substitution, and because of the current difficulties in the preparation of biologically important allyl diarylhosphonates, we also explore the use of those allyl silyl ethers by means of C-P bond formation. Inspired by both existing phosphonylation literatures and Ritter reaction, we developed a catalytic preparation method for those compounds which complements the existing methods with a high substituent flexibility under milder conditions. / Detailed summary in vernacular field only. / Chan, Chun Wa. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese. / Table of Contents --- p.i / Acknowledgement --- p.iv / Abstract --- p.v / Abstract (Chinese Version) --- p.vi / Abbreviation --- p.vii / Chapter CHAPTER 1 --- IMPORTANCE OF GREENER ALKENE SYNTHESIS AND INTRODUCTION OF NHC AND ITS APPLICATION IN 1,1-DSA SYNTHESIS --- p.1 / Chapter 1.1 --- Synthesis of Higher Alkenes with Different Substitution Patterns from Simple α-Alkene --- p.1 / Chapter 1.2 --- Introduction of NHC --- p.6 / Chapter 1.2.1 --- Electronic Property Comparison --- p.6 / Chapter 1.2.2 --- NHCMetal Complex Stability --- p.8 / Chapter 1.2.3 --- Steric Parameter Comparison --- p.9 / Chapter 1.3 --- Challenges in Using NHC-NiH as Hydroalkenylation (H.A.) Catalyst --- p.10 / Chapter 1.4 --- A New Solution for Catalytic NHC-NiH Based H.A. and 1,1-DSA Preparation --- p.14 / Chapter 1.5 --- Objective and Approach for Asymmetric Cross-H.A. --- p.18 / Chapter CHAPTER 2 --- PRELIMINARY STUDY ON LIGAND STRUCTURALACTIVITY-RELATIONSHIPS (SAR) --- p.21 / Chapter 2.1 --- Structural Criteria of Chiral NHCs for Asymmetric H.A. --- p.21 / Chapter 2.2 --- Successful Asymmetric H.A. Using Selected Chiral C2 Symmetric Ligands Rationalized by Stereo-Chemical Models --- p.24 / Chapter CHAPTER 3 --- STUDIES AND OPTIMIZATION OF CHIRAL C₁-NHC CATALYZED H.A. --- p.28 / Chapter CHAPTER 4 --- SECOND GENERATION OF CATALYST --- p.41 / Chapter 4.1 --- A New Lead: Substrates Electronic and Steric Effects on Ee --- p.41 / Chapter 4.2 --- Ee Enhancement by Using Electronic Modified N[superscriptAr] NHC --- p.48 / Chapter 4.3 --- Scope of Asymmetric Hydroalkenylation --- p.55 / Chapter 4.4 --- Conclusion --- p.62 / Chapter REFERENCE --- p.64 / Chapter APPENDIX (I) - --- ASYMMETRIC HYDROALKENYLATION --- p.71 / EXPERIMENTAL SECTION --- p.71 / GC CHROMATOGRAM --- p.178 / HPLC CHROMATOGRAM --- p.192 / Chapter REFERENCE OF APPENDIX (I) --- p.207 / Chapter APPENDIX (II) - --- APPLICATIONS OF ALLYL SILYL ETHER OBTAINED FROM HA CATALYST GENERATION: SELECTIVE PREPARATION OF ALLYL DIARYLPHOSPHONYLATION --- p.209 / Chapter A.1 --- Importance of Allyl Phosphonates --- p.209 / Chapter A.2 --- Conventional Methods and Challenges of Allyl Phosphonates Preparation with Higher Alkenes Functionality --- p.210 / Chapter A.3 --- Objective and Approach --- p.212 / Chapter A.4 --- Preliminary Results of Allyl Diarylphosphonylation --- p.213 / Chapter A.4.1 --- Strategies for Chemoselectivity Improvement --- p.215 / Chapter A.4.2 --- Proposed Mechanism: Ritter-like Reaction Pathway --- p.219 / Chapter A.5 --- Scope of Allyl Diarylphosphonylation --- p.222 / Chapter A.6 --- Introduction of Allyl Arylation --- p.228 / Chapter A.7 --- Scope of Allyl Arylation --- p.229 / Chapter A.8 --- Conclusion --- p.232 / EXPERIMENTAL SECTION --- p.234 / Chapter REFERENCE OF APPENDIX (II) --- p.274 / Chapter NMR --- SPECTRA COMPOUNDS FOR APPENDIX (I) -ASYMMETRIC HYDROALKENYLATION --- p.280 / Chapter COMPOUNDSFOR APPENDIX (II) - --- APPLICATIONS OF ALLYL SILYL ETHER OBTAINED FROM HA CATALYST GENERATION: SELECTIVE PREPARATION OF ALLYL DIARYLPHOSPHONYLATION --- p.388

Thesis (M. Sc.)--York University, 2000. Graduate Programme in Chemistry. / Typescript. Includes bibliographical references (leaves 78-83). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ59205.

No description available.

Thesis (Ph. D.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 142-148).

Thesis (Ph. D.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 118-123).

Thesis (M. Phil.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 72-75).

Thesis (Ph.D.)--University of Delaware, 2009. / Principal faculty advisor: Klaus H. Theopold, Dept. of Chemistry & Biochemistry. Includes bibliographical references.

This thesis work resulted from an on-going project in this laboratory focusing on the hydration of olefins, using transition metal complexes as catalysts, with the ultimate aim of achieving catalytic asymmetric hydration, for example: (HO₂C)CH=CH(CO₂H) → (HO₂C)CH₂-CH(OH)(CO₂H) (C = chiral carbon atom). Initially, the hydration of maleic to malic acid, catalyzed by Cr(H₂O)₆³⁺ at 100°C in aqueous solution was studied, including the kinetic dependences on Cr³⁺, maleic acid and pH. A proposed mechanism involving 1:1 complexes of Cr³⁺ with the maleato and malato monoanions is consistent qualitatively with the kinetic data. This Cr system was, however, ineffective for hydration of prochiral olefins, and the work became a minor component of the thesis and is described in the last chapter. Emphasis was switched to the study of water-soluble phosphine systems based on Pd and Pt. The major part of this thesis describes the synthesis and characterization, principally by ¹H, ³¹P{¹H} and ¹⁹⁵Pt{¹H} NMR spectroscopies, of: square-planar complexes of the type MX₂(PPh₃₋npyn)₂ (M = Pd, Pt; X = halides; n = 1, 2, 3); the binuclear species M₂X₂(µ-PPh₃₋npyn)₂ (head-to-tail, HT) and Pt₂I₂ (µ-PPh₃₋pyn)₂ (head-to-head, HH; n = 1,10a, n = 2, 10b and n = 3, 10c); and the Pt(PPh₂py)₃,27a, and Pt(Ppy₃)₃, 26c, complexes. The reactivities of the binuclear complexes toward acetylenes, and the Pt(0) species toward O₂, olefins, HCl and MeI, are also described. With use of PPhpy₂ within the binuclear phosphine-bridged species, the P atom incidentally becomes chiral. The diastereomers of 10b were isolated and characterized by ³¹P{¹H} NMR spectral data. All the isolated binuclear complexes react in CH₂Cl₂ with dimethylacetylene-dicarboxylate, DMAD, to form an A-frame insertion product. The HH or HT configuration of the precursor is maintained in every case except for 10b and 10c which form initially an HH-DMAD adduct that slowly isomerizes to the corresponding HT-DMAD adduct. Detailed ³¹P{¹H} NMR spectroscopic studies show that the presence of a properly positioned pyridyl group promotes the isomerization by forming a detectable chelated P-N intermediate, and that insertion of DMAD precedes chelation. The reactions of Pt₂l₂ (u-PPh₃₋npyn) ₂ (HH) (n = 1, 2, 3) with DMAD in CH₂CI₂ are kinetically first-order in both [Pt₂] and [DMAD] for the insertion step, and first-order in [Pt₂] and zero-order in [DMAD] for the isomerization step. The activation parameters for the insertion step are consistent with oxidative addition to a binuclear system. A proposed mechanism is fully supported by ³¹P{¹H) and ¹⁹⁵Pt{¹H] NMR spectral data. Complex 26c, reacts in CH₂CI₂ or CDCI₃ with limited oxygen to give Pt(Ppy₃)₃(O₂), which may contain an end-on superoxo structure as judged by an IR band at 1114 cm⁻¹. Complex 26c, under 1 atm O2, forms the 'expected' peroxo species Pt(Ppy₃)₂O₂. Complexes 26c and 27a, react with the olefins (maleic anhydride, acrylonitrile, methacrylonitrile and crotonitrile) to give the square-planar species Pt(PPh₃₋npyn) ₂(ɳ²-olefin). The square-planar geometry infers strong Π-back donation from metal to olefin, a state which is probably undesirable for the purpose of olefin activation toward hydration. Indeed, complex Pt(PPh₂py) ₂(Π²-maleic anhydride), 47a, shows no olefin hydration product when heated at 80°C in aqueous NaOH solution. Trans-Pt(H)Cl(PPh₂py) ₂, 50a, was prepared from 27a and gaseous HCl in THF; 50a in acetone-d6, reacts with acrylonitrile to give cis-PtCl(CH₂CH₂CN)(PPh₂py)₂, but in the presence of aqueous NaOH at 80°C, 50a was inactive for hydration of acrylonitrile to either β-cyanoethanol or acrylamide. / Science, Faculty of / Chemistry, Department of / Graduate

The formation of 1:1 π-complexes between chlororuthenate(II) and a series of substituted ethylenes in aqueous hydrochloric acid solution is described. Kinetic studies of the complexation for maleic, acrylic and crotonic acid substrates are presented. The likely mechanism is a two step process involving an initial S[subscript]N¹ dissociation of a chlororuthenate(II) complex or complexes. The nature of the blue chlororuthenate(II) species is uncertain and this prevents resolution of some questions about the mechanism; however, observations on the behavior of the blue solutions and some suggestions as to their possible nature are given. Acrylic and crotonic acids are hydrogenated catalytically via the ruthenium(II) π-complexes. Crotonaldehyde and crotonitrile complexes of chlororuthenate(II) are not hydrogenated but undergo hydration and/or polymerization. Kinetic data for the hydrogenation of the organic acids fit a well established mechanism. The factors which influence reaction rates in the hydrogenation steps are thoroughly discussed. / Science, Faculty of / Chemistry, Department of / Graduate

The thermal decomposition of cis- and trans-3-methyl-4-ethyl-3-carbo-methoxy-Δ¹-pyrazoline (cis- implies that the methyl and ethyl groups are cis) and trans-3-methyl-4-ethyl-3-carbomethoxy- Δ¹-pyrazoline gave a mixture which contained cyclopropane products, cis- and trans-1-methyl-2-ethyl-1-carbo-methoxycyclopropane; α, β-unsaturated ester products, methyl cis- and trans-2,3-dimethyl-2-pentenoate (cis and trans refer the two methyl groups); and the β, у-unsaturated ester, methyl 2-methyl-3-ethyl-3-butenoate. The α,β-unsaturated esters are formed stereospecifically since cis-3-methyl-4-ethyl-3-carbomethoxy-Δ¹-pyrazoline gave only methyl trans-2,3-dimethyl-2-pentenoate (56% in the liquid phase and 28% in the vapor phase). Similarly in the pyrolysis of trans-3-methyl-4-ethyl-3-carbomethoxy- Δ¹-pyra-zoline methyl cis-2,3-dimethyl-2-pentenoate (13% in the liquid phase and 6% in the vapor phase) was obtained while only a trace of methyl trans-2,3-dimethyl-2-pentenoate was found in both the liquid and vapor phase pyrolysis. The cyclopropane products formed from pyrolysis of cis- and trans-3-methyl-4-ethyl-3-carbomethoxy- Δ¹-pyrzaoline have shown some degree of stereo-specificity with a predominance of the isomer having the same stereochemistry as the starting pyrazoline being obtained. The results of the above experiments suggest that the mechanism of thermal pyrolysis of pyrazolines requires that the nitrogen leaves from the same side as the ethyl group, i.e. trans to the hydrogen which is migrating. The photolysis of cis- and trans-3-methyl-4-ethyl-3-carbomethoxy- Δ¹-pyrazoline has been found to be stereospecific in cyclopropane formation with the absence of isomeric olefin products. A small amount of the olefin corresponding to loss of CH₂N₂ was also found having the same stereochemistry as the pyrazolone. Since the products from photolysis are different from that of pyrolysis, a modified mechanism is required. Insufficient evidence is available to clearly define that mechanism. / Science, Faculty of / Chemistry, Department of / Graduate