Interaction of triphenylphosphine with Ni(XqO)2 (XqOH = 2-nitrosophenol, X = 4-chloro, 4-bromo, 4-methyl and 5-methoxy) resulted in deoxygenation to give mainly bis(2-triphenylphosphiniminophenolato) nickel(ll), Similarly the interaction of triphenyl phosphine with Zn(qO)2 (qOH = 5-methoxy-2- nitrosophenol) involved deoxygenation and formation of bis(2-triphenylphosphiniminophenolato)zinc(ll). Action of dilute hydrochloric acid on these complexes afforded the hydrochlorides of the corresponding N(2-hydroxybenzene)iminotriphenyl phosphoranes. The hydrochlorides on neutralisation with sodium carbonate gave, in most cases, the parent N(2-hydroxybenzene)- iminotriphenyl phosphorene.

X-ray analyses of fifteen carbonyl clusters of ruthenium and osmium have been completed which demonstrate several new aspects of cluster structure.

The reaction of 5-hydroxy-2-nitrosophenol (mnrH), 5-hydroxy-6-methyl-2-nitrosophenol (6-MemnrH). 2 4-dinitrosooresorcinol (dnrH2) and substituted dinitrosoresorcinols (X-dnrH2) with various metal salts gave monomeric, dimeric and polymeric metal complexes such as M(mnr)2 (M=Cu, Ni and Fe); Cu(OH)(mnr); M(dnr)(M=Ni or Cu). The complexes of type M(mnr)j , M(6-Memnr)2 and M(dnr) (M=Cu or Ni) form 1:2 adducts with pyridine. These complexes were investigated using spectroscopic, thermogravimetric and magnetochemical techniques, and where appropriate by Mossbauer spectroscopy. The complexing behaviour of 3-methyl-4-oxime-IH-pyrazol-4, 5-dione (poH) and 3-methyl-4-oxime-l-phenvl-lH-pyrazol-4,5-dione (PpoH) with nickel(II) and copper(II) has been reinvestigated. Three new iron(II) complexes derived from these ligands have been prepared either by the reaction of PpoH with iron(II) under aqueous conditions or by the reaction of poH with iron pentacarbonyl in anhydrous THF. The latter reaction also afforded a number of organic products, the formation of which has been rationalised in terms of nitrene intermediates. The complexes Fe(Ppo)2.H2O, Fe(Ppo)2 .2py and Fe(po)2.H2O were found to be high spin. This property contrasts the behaviour of iron(II) complexes derived from 2-nitrosophenols, which are low spin, and is rationalised in terms of conjugation effects and the bonding character of the pyrazol-4, 5-dione monooxime ligand. The interaction of Cu(mnr)2. 2py with triphenylphosphine gave several products including a phenoxazinone and a novel phenoxazinone phosphorus ylid whose structure was elucidated by X-ray crystallography. The complex Cu(6-Memnr)2. 2py behaved similarly towards triphenylphosphine. The synthetic significance of these reactions is discussed. Kinetic studies on the reaction between triphenylphosphine and Cu(mnr)2 .2py indicate that adduct formation takes place initially. It is suggested that subsequent deoxygenative decomposition of this adduct leads to the products. Attempts to clarify the proposed mechanism through the use of insoluble polymer supports were not fruitful.

A stirred flow reactor was adapted to study the rate of formation of hydrocarbons in the low pressure, 10mmHg, oxidation of propanal, n-butanal and iso-butanal over the temperature range 710-783K.

The synthesis of 1,2-naphthoquinone I-oxime and 1,2- naphthoquinone 2-oxina complexes of rhodium and Iridium has been Investigated. In the case of rhodium, complexes of the type Rh(l-nqo)3 have been prepared by reacting 1 ,2-naphthoquinone 1-oxime with hydrated rhodium(III) chloride. Both products ware obtained as mixtures of isomers. The Interaction of 1,2- naphthoquinone 2-oxime with rhodium(lll) chloride yielded Rh(2-nqo)3 also as a mixture of Isomers. The trichelates were also obtained from the nitrosation of the appropriate naphthol in the presence of rhodium(Ill) chloride. In contrast, the corresponding reaction systems involving iridium gave very complex mixtures Involving both iridium containing species and organic products. One of the iridium products, [pyH][lr(1-nqo)C13 pyl, has been isolated in the pure state and characterised by X-ray crystallography. The complexes Ir(1-nqo)3 and lr(2-nqo)3 were also isolated but in low yields. All trichelates ware shown to be diagmagnetic. None reacted with either pyridine or triphenylphosphine. These observations have been rationalised in terms of crystal field stabilisation energy. The behaviour of the rhodium and iridium complexes towards the Lewis bases contrasts that of analogous iron and cobalt complexes. The X-ray study of [pyH][lr(l-nqo)C13 py] has shown that the ligand is chelated to the metal as been observed in first transition series metal complexes derived from such ligands. The use of 1,2-naphthoqulnone 1-oxime as a potential ligand for separating rhodium from iridium has been investigated. Optimum conditions for recovery of rhodium was established, as a technique for refining rhodium current process at Inco (Europe) Ltd. The synthesis of cobalt, rhodium, copper, iron and nickel complexes of 1 ,2-naphthoquinone l-oxime-3,6- disulphonic acid (nRsH3) has been investigated and the complexes were isolated in solid form by developing a separation technique. Cobalt(III) and rhodium(III) salts reacted with the ligand to give metal complexes of type M(nRs Na)3 . The behaviour of the 1,2-naphthoquinone 1- oxime-3,6-disulphonic acid towards iron(ll) and iron(lll) or copper salts was shown to be more complex and interesting than previously reported. Both iron(II) and iron(III) chloride gave an Iron(II) product of the type Fe(nRs Na) whilst Iron(II) ammonium sulphate gave an Fe(II) product of the type Fe(nRs Na)2. The nickel salts gave a complex containing two ligands per metal, Ni(nRsHNa)2. The complexes of Iron(II) and copper(Il) of 1 ,2-naphthoquinone l-oxime-3,6-disulphonic acid catalysed aerobic oxidation of catechols. The oxidation involved oxidative cleavage of the aromatic ring of catechol by molecular oxygen to give muconic acid anhydride and 2H-pyran-2-one in addition to benzoquinone. This behaviour is very similar to enzyme catalysed oxygenation.

The development of an effective test system for detecting the irradiation status of foodstuffs is essential for the establishment of legislative control and consumer choice. For foodstuffs consisting mainly of water, treatment with ionising radiation initially generates highly reactive free radical species (hydroxyl radical (‘OH), hydrated electrons (e-aq) or hydrogen atoms (H)). These react extremely rapidly with a wide variety of “target" molecules in foodstuffs resulting in small but detectable chemical changes. Hence, assays for the assessment of ‘OH radical activity involve the identification and/or quantification of chemical species produced by the attack of ‘OH radical on a range of biomolecules occurring in foodstuffs. This study Involves an investigation of radiolytically-induced chemical modifications arising from the Interaction of ‘OH radical with naturally occurring aromatic compounds in fruits and vegetables. High performance liquid chromatography coupled with electrochemical detection has been applied to the analysis. In addition, the chemical nature of intermediates in, and end-products arising from the interaction of ‘0H radical with polyunsaturated fatty acids and carbohydrates Is reviewed by application of second-derivative (2D) electronic absorption spectrophotometry. The 2D spectrophotometric technique has not been previously applied to food studies and may serve as a potential “probe” for the measurement of radiolytic products generated as a consequence of irradiation treatment. Additionally, high-field, high-resolution proton nuclear magnetic resonance spectroscopy has been employed to assess radiolytically-induced damage to biomolecules present In shellfish.

Glutamic and aspartic acids are considered to be potent excitatory amino acid neurotransmitters of vertebrates. Receptors for these amino acids may be sub-divided into three types: (i) Quisqualate/glutamate, (ii) N-methyl-D-aspartate (NMDA) and (iii) Kainate type. The aim of this project has been to develop specific mimetics which act only at one defined site. In particular, attention has been focused on the two former sub-groups. It has been shown that 2-amino-5-phosphonopentanoic (APP) and 2-amino7-phosphonoheptanoic (APH) acids are very potent NMDA antagonists and anticonvulsants and in order to further the pharmacological study of this class of compound, efficient synthetic routes have been developed which afford the compounds in high overall yields. APB(2-amino-4-phosphono-butanoic acid), APP and APH can now be obtained in 10-50 g quantities which has permitted the evaluation of these compounds in a variety of animal models of epilepsy closely related to those in man. A study focused on photically stimulated seizures in the baboon has shown APP and APH to be particularly effective. This model is thought to be one of the closest to human seizures. Quinolinic acid (Quin), an endogenous excitant and neurotoxin, may be classified as an NMDA type compound. The aim of this project has been to develop analogues of Quin, some of which may well be specific antagonists of NMDA. The higher homologue (1) of Quin has been s3rnthesised and has very recently been shown to be at least twelve times more potent than Quin as a neurotoxin. A series of homologues are to be synthesised, the synthesis of homologue (2) is now being completed. The peptide derivative (3) and its phosphonate analogue (4) have recently been synthesised and experiments are now in progress to determine their potency. Tricholomic acid (TA)(5), an amino acid extracted from Tricholoma muscarium, has been suggested to be a very potent neuroexcitant of the quisqualate/glutamate sub-division by some Japanese workers. However, studies on this compound and the development of putative mimetics have been hindered by the lack of any reasonable synthetic route to TA. Such a route has now been devised and TA has been synthesised.

A number of 1-aminoalkanephosphonic acid derivatives incorporating physiologically Iabile groupings (ester, amide e.g. peptide, carbamate and tosyl) were prepared as a development from earlier studies in which certain phosphonic acid derivatives were shown to have previously unrecognised activity as fungicides. Such derivatisation might aid the translocation of the active phosphonic acid to the site of action. Compounds were screened for in vivo fungicidal activity against Drechslera teres. Drechslera graminae. Drechslera avenae. Prythium ultlmum. Rhizoctonia solani. Fusarium culmorum. Pyricularia oryzae, Puccinia recondita. Erysiphe zraminis[?] and Septoria nodorum. Results showed that all the phosphonopeptides prepared had moderate to good antifungal activity, with the L-alanine di- and tripeptides of l-aminopropanephosphonic acid having superior activity to the commercial fungicide imazalil when tested against D. teres and D. avenae. The proton, carbon-13 and phosphorus-31 nmr spectroscopy of the compounds prepared was examined in detail with carbon-13 proving particularly useful. The carbon-phosphorus coupling constants varied along the alkyl chain in the phosphonopeptides with JPC=145-148 Hz, JPCC=0 Hz , JPCCC=12-14 Hz and JPCNC=4-6 Hz. The use of Fast Atom Bombardment mass spectrometry has proven to be successful for the characterisation of aminophosphonic acid derivatives, especially phosphonopeptides, with the MH ion normally being the base peek. Phosphonopeptides give characteristic fragmentation patterns due to the sequential loss of [alpha]-lactam units arising from the amino acid chain. A number of routes to the preparation of l-aminoalkanephosphonic acids were investigated, in particular those routes utilizing 1-ozo-alkanephosphonates, and a detailed study into the hydrogenation of dialkyl l-hydroxyiminoalkanephosphonates using Raney Nickel and, more successfully, palladiua-on-carbon catalysts was undertaken. Preliminary attempts were made to prepare phosphonopeptides via the previously unexamined route of solid phase synthesis and some of the difficulties involved with this method are discussed.

This thesis describes apparatus and techniques for making ultrasonic measurements in fluids and applications of them to measurements of ultrasonic parameters in colloidal dispersions. A brief description of the properties and uses of ultrasound propagation in dispersions is followed by an extensive review of theories which relate the particulate properties of the dispersions to the measurable ultrasonic parameters, velocity (c) and attenuation (a [alpha]). Measurement principles are outlined related to the design of near-field measurement methods and the development of three techniques is described. These are shown 10 give results which are both highly self-consistent and in excellent agreement with a far-field method. Measurements of a[alpha] and c for model dispersions of glass spheres in Newtonian Iiquids are shown to be in good agreement with the relevant theory when particle polydispersity is taken into account. For structured fluids as the continuous phase, the a[alpha] and c data for suspensions of spheres are used to obtain the continuous phase viscosity (n). The a[alpha] data agree approximately with the macroscopic viscosity, but the velocity data requires the introduction of a shear elastic term and the revision of theory in order to obtain agreement. Attenuation as a function of barite concentration in Newtonian liquids was investigated and the ultrasonic particle radius was found to be systematically larger than expected. This is attributed to particle rugosity. Measurements of a[alpha] and c using non-gelling aqueous kaolinite suspensions are shown to agree well with theory when the eccentricity and the interactions of particles are taken into account. For gelling aqueous bentonite suspensions, a[alpha] and c were found to be time-dependent over a period of several days following initial dispersion. The observed increases in both a[alpha] and c are interpreted in terms of a growth in gel fraction and shear modulus, respectively. The effect of shear flow on a[alpha] and c was investigated for the above dispersions. Changes were barely resolvable but consistent with shear-degradation of structure within the fluid.

The reaction between N,N,N‘,N'-tetramethylphosphoric triamide (TMPT) and chloral has been shown to give chloroform, dimethylformamide, (Me2N)2P(0)NHCH(CCl,)NMe2 and polymeric phosphorus containing compounds. A possible mechanism for the formation of these products is given.