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Item Iminophosphine ligands and their metal binding properties : a thesis presented in partial fulfilment of the requirements for the degree of Science in Chemistry at Massey University, Palmerston North, New Zealand(Massey University, 2003) McBeth, Kurt AllenThis work focuses on the complexes of two iminophosphine ligands, N-(2-diphenylphosphinobenzylidine)-aniline (NP) and N-(2-diphenylphosphinobenzylidine)-4'-(benzo-15-crown-5) (O₅NP), and their complexes with Cu(I), Ag(I), Au(I), Cr(0), Mo(0) and W(0). The cation binding properties of the complexes of O₅NP have been investigated. Chapter One describes the aims of this work and also provides a brief introduction to ligands containing phosphorus and nitrogen donor atoms as well as crown ethers and their inclusion in transition metal complexes. The analytical technique of electrospray mass spectroscopy (ESMS) is introduced and its use in the study of cation binding to crown ethers and cryptands discussed. Chapter Two looks at the Cu(I), Ag(I) and Au(I) complexes of NP and O₅NP, such as [M(L)₂][PF₆] (M = Cu, Ag, Au; L = NP, O₅NP), [M(NP)X]₂, [M(O₅NP)Cl]₂ (M = Cu, Ag), Au(NP)X and Au(O₅NP)Cl (X = Cl, Br, I). Reported in this chapter are the X-ray structural analyses of O₅NP, [Cu(NP)₂][PF₆], [Ag(NP)₂][PF₆], [Au(NP)₂][PF₆], [Cu(NP)Br]2, Au(NP)Cl and Au(NP)Br. Far and Near IR, ¹H and ³¹P NMR and ESMS were used to investigate the nature of the complexes. The [M(L)₂][PF₆] complexes displayed a clear trend in which the number of coordinated imines decreased as the soft nature of the metal centre increased. Both the Far IR and crystal structure analyses showed the Cu(I) and Ag(I) halo complexes to be dimeric with bridging halides and the Au(I) halo complexes to be monomeric with terminal halides. The ³¹P NMR signal was found to be dependent on the mass of the metal centre. In Chapter Three the Cr(0), Mo(0) and W(0) carbonyl complexes of NP and O₅NP are discussed. To characterise the complexes, IR, ESMS and ¹H, ³¹P and ¹³C NMR techniques were employed. X-ray structural analyses of Mo(CO)₄(NP) and Mo(CO)₄(O₅NP) were also used. It was found that the metal centres had an octahedral geometry with the ligands being bidentate via the P and N atoms and having a cis conformation. Upon coordination, the ¹H NMR signal of the imine proton moves to lower frequencies, whereas the ³¹P NMR signal moves to higher frequencies. It was also demonstrated that the presence of the crown ether has no significant effect on the structure of the metal centre. Cation binding to the complexes of O₅NP, the free ligand, and starting material, 4'-aminobenzo-15-crown-5 (O₅NH₂), is discussed in Chapter Four. Electrospray mass spectroscopy (ESMS) was used as a qualitative measure of the relative cation binding strengths. The X-ray structural analyses of the inclusion complexes W(CO)₄(O₅NP)Na(PF₆) and [Cu(O₅NP)₂]K.[PF₆]₂ were determined, and provided information on the coordination of alkali cations by these complexes. W(CO)₄(O₅NP) binds Na⁺ within the cavity of the benzo-15-crown-5 moiety which experiences significant change to its conformation. [Cu(O₅NP)₂][PF₆] binds K⁺ in a sandwich formation suggesting that rotation of the ligands occurs about the Cu(I) centre. The starting material, O₅NH₂, and free ligand, O₅NP, were selective towards K⁺, forming a 1:1 species. The complexes M(CO)₄(O₅NP) (M = Cr, Mo, W) and [M(O₅NP)₂][PF₆] (M = Cu, Ag, Au) were selective towards Na⁺ and K⁺ respectively with a 1:1 formation. The halide complexes, [Cu(O₅NP)Cl]₂, [Ag(O₅NP)Cl]₂ and Au(O₅NP)C1, displayed different selectivities from each other. Both [Cu(O₅NP)C1]₂ and [Ag(O₅NP)Cl]₂ dissociated in solution to give the monomers which selectively bound Li⁺ and K⁺ respectively in a 1:1 species. The Au(O₅NP)Cl complex was selective towards Na⁺.Item Phosphine-porphyrin conjugates : a thesis presented in partial fulfilment of the requirements for the degree of Masterate of Science in Chemistry at Massey University, New Zealand(Massey University, 2000) Lun, David JamesThe research carried out in this thesis comprises an investigation into the synthesis and characterisation of a variety of complexed phosphine-aldehydes, complexed phosphinoporphyrins, and phosphinoferrocene conjugates. The porphyrin and phosphine moieties are linked together via the vinyl group, a product of Wittig chemistry. In general, functionalisation occurs at the β-pyrrolic position of the porphyrin and at the para position of a phenyl group on the phosphine. Chapter One introduces the properties of porphyrins and the triphenylphosphine ligand, as well as a brief review on the types of functionalised triphenylphosphines. A brief review of existing phosphinoporphyrins is also discussed. The proposal for using the vinylic linking group (and hence Wittig chemistry) to connect the porphyrin and the phosphine moieties is also described. Chapter Two outlines the synthesis of the 4-(diphenylphosphino)benzaldehyde (5) ligand, which is a necessary precursor for the Wittig reaction with meso-tetraphenylporphyrin (TPP) phosphonium salt (1). It was discovered that the Wittig reaction of (1) with (5) led to the synthesis of the product of oxidation, phosphinoporphyrin oxide (7), instead of the desired phosphinoporphyrin (6). Therefore an alternative scheme was pursued - complexation before the Wittig reaction. Hence the remainder of the chapter describes both the synthesis and characterisation aspects of five transition metal complexes of (5). These include complexes of gold, ruthenium, tungsten, and platinum. Chapter Three describes the synthesis and characterisation of a variety of novel complexed phosphinoporphyrins, including two bis-phosphinoporphyrin complexes. This was achieved by utilising Wittig chemistry of TPP phosphonium salt (1) with the appropriate complexed phosphine-aldehyde. In each case, optimisation of the Wittig conditions was required in order to obtain the sterically and thermodynamically favoured trans isomer. Chapter Four extends the phosphinoporphyrin chemistry by investigating the synthesis of a novel phosphinoporphyrin trimer. In order to achieve this, a phosphine tris-aldehyde was synthesised. This chapter focuses on the synthesis and characterisation of tris(4-formylphenyl)phosphine oxide (20). The results of the Wittig reaction of (20) with TPP phosphonium salt (1) are also described. Chapter Five demonstrates the versatility of both the Wittig and phosphine chemistry. In this chapter, the synthesis of phosphinoferrocenes via Wittig chemistry is investigated. The ferrocene and phosphine moieties are linked via the vinyl group, in a similar manner as the phosphinoporphyrins. In this case, functionalisation occurs at the para position of a phenyl group of the phosphine to the cyclopentadienyl ring of the ferrocene. A phosphinoferrocene monomer, (24), was synthesised by Wittig reaction of a ferrocene phosphonium salt (22) with (5). Both the synthesis and characterisation of this compound is reported. Also described is the attempted synthesis of a phosphinotrisferrocene via Wittig reaction of (22) with (20). Chapter Six contains a brief summary of the results obtained during this study, and also mentions future research to be pursued in this field of study.Item A study of new planar chiral monophosphine ligands based on [2.2]paracyclophane and their use in catalysis : Chemistry, Institute of Fundamental Sciences, Massey University : Masters thesis under the supervision of Dr. Gareth J. Rowlands(Massey University, 2011) Wang, Jingjing; Wang, JingjingThe Suzuki-Miyaura coupling reaction is one of the most powerful methods for the construction of biaryls. The biaryl motif has great importance in pharmaceutical, agrichemical and material science industries, and is often axially chiral. The outcome of a Suzuki-Miyaura coupling reaction can be influenced by many factors, but the ligand plays the most vital role. A large number of ligands have been developed, including many chiral ligands for asymmetric reactions. While ligand design has focused on molecules containing either central or axial chirality, little has been focused on planar chiral ligands. In this project, three new ligands based on the [2.2]paracyclophane backbone have been designed, pseudo-ortho substituted monophosphines (L1 and L2), secondary phosphine oxide and arylindolyl phosphine ligands (L3 and L4). Unfortunately, similar analogues of L1 and L2 were reported before our results, and a synthesis route to the secondary phosphine oxide ligands was not achieved. The use of L1 in gold mediated cyclisation was investigated, which concluded that L1 was not suitable for this kind of reaction. However, arylindolyl phosphine ligands were prepared successfully, and produced promising preliminary results in achiral Suzuki-Miyaura coupling reactions. Interesting X-ray crystallography structure of brominated indole is discussed.