Yu Michael. / Thesis submitted in: July 2003. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 57-63). / Abstracts in English and Chinese. / Table of Contents --- p.i / Acknowledgments --- p.iii / Abbreviations --- p.iv / Abstract --- p.v / Chapter Part I - --- Optimization of Palladium Catalyzed Phosphination / Chapter Chapter 1 --- General Introduction / Chapter 1.1 --- Background of Phosphine Synthesis --- p.1 / Chapter 1.2 --- Preparation of Phosphines --- p.4 / Chapter Chapter 2 --- Optimization of Phosphination of Aryl Bromides / Chapter 2.1 --- Additive Effect in Phosphination of Aryl Bromides --- p.14 / Chapter 2.2 --- Iodide Effect in Phosphination of Aryl Triflate --- p.25 / Chapter 2.3 --- Low Temperature Phosphination --- p.27 / Chapter 2.4 --- Conclusion --- p.29 / Chapter Part II - --- Synthesis of Optically Active As，N Ligands and Their Metal Complexes / Chapter Chapter 1 --- 3.1 Introduction --- p.30 / Chapter Chapter 2 --- Synthesis of Optically Active As，N Ligands and Their Metal Complexes / Chapter 4.1 --- "Synthesis of As,N Oxazolines" --- p.39 / Chapter 4.2 --- "Synthesis of As,N Oxazoline Transition Metal Complexes" --- p.41 / Chapter 4.3 --- Conclusion --- p.44 / Experimental --- p.45 / References --- p.57 / Appendix --- p.64

The organometallic chemistry of C60 has attracted much attention concerning the effect of metal coordination on the properties of C60 since the discovery and macroscopic synthesis of C60. In our study, we try to synthesize two analogous ligands which contain two phosphines. And reaction of the new ligands and metal carbonyl clusters will produce new-type of metal complexes. Addition of Ph2(Li)PBH3, prepared by n-BuLi-deprotonation of Ph2(H)PBH3 in THF, to toluene solution of C60 took place to give the adduct C60H2(Ph2PBH3)2 (2) after quenching with HCl in ethyl acetate. Reaction of C60 and sodium 1-propanethiolate in acetonitrile produces C602-, and then adding PPh2Cl to C602- solution to afford C60(PPh2)2 (8). Treatment of the borane complex 2 with diazabicyclo[2.2.2]octane (DABCO) in toluene removes the borane group to give the phosphine C60H2(PPh2)2 (3). Reaction of 3 and Os3(CO)10(NCMe)2 at room temperature produces Os3(CO)10(£g,£b3-(PPh2)C60H) (5) and C60H2(PPh2)2(Os3(CO)10)2 (6). Furthermore, reaction of 3 and Ru3(CO)12 at 85 ¢J produces Ru3(CO)10(£g,£b3-(PPh2)C60H) (7). The resulting compounds are characterized by NMR, IR, Mass, X-ray and EA.

A series of nickel(II) and Pt(II) complexes supported by the bis(2-diphenylphosphinophenyl)amide ligand, [PNP]¢w have been prepared. In Nickel(II) chemistry, the halide complexes are both air and water stable. The nickel(II) alkyl and aryl derivatives were presented including those in which the alkyl contains

The preparation and structural characterization of a series of Tantalum complexes supported by 2,2¡¦-phenylphosphinobis(4,6-di-tert-butyl- phenolate) ([OPO]2-) are described. The reaction of Li2[OPO] with TaCl5 produced yellow crystals of [OPO]2TaCl, regardless of the stoichiometry of the starting materials employed. Alkylation of [OPO]2TaCl with a variety of Grignard reagents generated [OPO]2TaR (R = Me, Et). Formation of [OPO]2TaH arise from [OPO]2TaEt undergo £]-Hydrogen elimination at 120 oC or reaction of [OPO]2TaCl with LiHBEt3. The solid-state structures of [OPO]2TaCl, [OPO]2TaOH and [OPO]2TaH and the solution of these Tantalum complexes were characterized by X-ray crystallography and multinuclear NMR spectroscopy. A new chelating N, N ligand family incorporation an anilido- phosphinimine donor set has been designed. The ligand 1-(NHAr)-2-(PPh2=NAr)C6H4 ([NN-iPr]; Ar = 2,6-diisopropylphenyl) was prepared by Staudinger reaction with 2,6-diisopropyl- phenylazide and N-(2-diphenylphosphinopheyl)-2,6-diisopropyl-anilide. Deprotonation of H[NN-iPr] with n-BuLi in THF at -35 oC generated [NN-iPr]Li(THF). The reactions of trialkylaluminum with H[NN-iPr] produced the corresponding dialkyl complexes [NN-iPr]AlMe2 and [NN-iPr]AlEt2. The aluminum complexes were all characterized by 1H, 13C{1H}, 31P{1H}, and 27Al{1H} NMR spectroscopy. The solid-state structures of H[NN-iPr] and [NN-iPr]AlMe2 were determined by X-ray crystallography.

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The success of homogeneous asymmetric catalysis has been attributed to the structure and stereochemistry of the coordinated ligand(s). The most effective ligands are C₂-symmetrical bisphosphines containing either a rigid chiral backbone linking two PPh₂ units or a bisphosphine, DIPAMP containing two chiral phosphine units linked by an achiral backbone. The synthesis of P-chiral ligands of this type has been severely hindered by the lack of a general synthetic route allowing the incorporation of phosphorus chirality without the need for separation of diastereomeric precursors or resolution of intermediate enantiomers. The objective of this work was to develop a general synthetic route to homochiral bulky arylphosphines with substantial flexibility in the groups at phosphorus and extend the approach to new P-chiral bisphosphines. In one approach, diastereomerically pure (2R, 4S, 5R)-2,5-diphenyl-3,4-dimethyl-1,3,2-oxazaphospholidine was prepared directly from PhPCl₂ using l-ephedrine as a chiral auxiliary. Stereospecific oxidation using Bu^tOOH gave the corresponding P-oxide which was shown to have R-stereochemistry at phosphorus by single-crystal X-ray diffraction studies. The compound reacted regiospecifically with ortho-anisylmagnesium bromide to afford the product formed by P-O bond cleavage with >96% d.e. and with retention of configuration at phosphorus as demonstrated by single-crystal X-ray diffraction studies. The l-ephedrine residue was replaced by O-methyl under acid-catalysis with inversion of configuration and with >95% e.e., the reaction was monitored by ¹H n.m.r. spectroscopy which gave t_1/2 of ca. 30 min. Attempts to incorporate para-fluorophenol using similar conditions led to the isolation of the pyrophosphinate in low yield. The OMe residue in the methyl (ortho-anisyl)phenylphosphinate was readily displaced by aliphatic Grignard reagents giving the corresponding phosphine oxides with inversion of configuration and with >95% e.e. Displacement of methoxy using aryl magnesium bromides showed similar enantioselectivity but in lower chemical yield, however the corresponding arylmagnesium chlorides were more efficient. In a second approach, diastereomerically pure (2R, 4S, 5R)-2-chloro-3,4-dimethyl-5-phenyl-1,3,2-oxazaphospholidine was prepared from PCl₃ and l-ephedrine. The compound underwent diastereoselective P-C1 cleavage with aryl Grignard and aryllithium reagents with net retention of configuration at phosphorus and with 90% d.e. Oxidation of the ortho-anisyl derivative afforded (2R, 4S, 5R)-2-(ortho-anisyl)-3,4-dimethyl-5-phenyl-1,3,2-oxazaphospholidine-2-oxide which was subsequently reacted with a range of bulky aryl Grignard reagents to afford the corresponding biarylphosphinamides with retention of configuration at phosphorus. Subsequent acid-catalysed methanolysis and displacement of the methoxy residue with PhMgCl afforded a range of bulky arylphosphine oxides with defined configuration at phosphorus with >95% e.e. as determined by ¹H n.m.r. methods. (S)-ortho-anisyl (meta-anisyl)phenylphosphine oxide underwent regiospecific ortho-lithiation on the meta-anisyl ring which on quenching with D₂O afforded the corresponding 2-deuteride in 80% yield. The 2-iodo analogue was also prepared although in low chemical purity and is a key precursor to new axially dissymmetric bisphosphines containing chiral phosphorus centres. Other approaches to P-chiral ferrocenyl ligands and biaryl ligands are also described and modifications for further development are implicated. An X-ray crystallographic study of six aryl-oxazaphospholidines is also presented and demonstrates the influence of the substituents at phosphorus in determining the conformation of the 1,3,2-oxazaphospholidine ring. A comparison with solution ¹H n.m.r. data showed, in some cases, good correlation between the P-O-C-H dihedral angle and the corresponding solid state torsion angle.

Thesis (Ph.D.) in Chemistry--University of Maine, 2007. / Includes vita. Includes bibliographical references (leaves 263-273).

Thesis (Ph. D.)--University of Michigan, 1932. / Cover title. "Reprinted from the Physical review, volume 45, no. 4, February 15, 1934."