A potential industrial process is profitable only if it is successfully implemented by the continuously developing chemical industry. Throughout last decades heterogeneous catalysis has opened doors to the creation of various know-how products which previously were considered unfeasible. Moreover, the use of heterogeneous catalysts allows improving existing processes to shift towards more ecological and cost efficient practices. In particular, polymer or fuel compounds could be eco-friendly produced from wood extractives, as an alternative to the conventional oil resources. This goal becomes even more attractive in light of the upcoming peak-oil. In the Nordic pulping industry turpentine is widely available as a tonnage by-product. Despite its interesting properties and promising application possibilities this fraction is commonly burned in the recovery boilers for energy. Although the chemical composition of turpentine depends strongly on the specific pulping process, α-pinene is the predominant compound and as such most studied. The general message of this thesis is the successful implementation of the heterogeneous catalysts in one-pot value-added upgrading of crude turpentine and specific terpenes, particularly α-pinene. Concepts allowing the production of fragrances, resins, plastics and pharmaceutical compounds are presented in the current study. Both commercial (Amberlyst 70) and self-prepared (Me/Al-SBA-15 or TiO2) catalysts were studied in several reactions including: acetoxylation, isomerization, dehydroisomerisation and oxidation. Both commercially purified α-pinene and crude thermo-mechanical turpentine were used as raw materials in the catalytic one-pot synthesis of value-added compounds. The experiments were performed in both batch and continuous reactor systems depending on the studied reaction. Successful results were obtained in case of several reactions. As an example, upon acetoxylation of α-pinene valuable fragrances – α-terpinyl and bornyl acetates – were produced with yields of 35 and 40 wt-%, respectively. Furthermore, in the dehydroisomerisation reaction of α-pinene, a yield of around 80 wt-% of an important fragrance, solvent and plastics precursor, ρ-cymene, was obtained. In the last case, thermo-mechanical turpentine was also successfully utilized. Still, some α-pinene oxidation tests leading to α-pinene oxide and verbenone fragrances were also carried out. Upon this study, further oxidation of ρ-cymene lead to the formation of ρ-methyl-acetophenone, a product essential for perfumery, pharmaceutical and pesticide industry as well as a potent polymer precursor. In addition, isomerization reactions were performed. Additionally, the catalytic materials were thoroughly characterized and analyzed.

Biodiesel is a renewable and biodegradable alternative green fuel for petroleum-based diesel. The major obstacle for the production of biodiesel at an industrial scale is the high production cost, which is related to the relative high price of the conventional ???1st generation feedstocks??? (refined vegetable oils) used. This problem can be addressed by using low cost feedstocks such as waste oils and fats. However, these feedstocks contain high amounts of free fatty acids (FFA) which cannot be used for the production of biodiesel using a traditional homogeneous alkali-catalyzed transesterification process. Furthermore, there is a great need to develop a green process which can be used for multiple feedstocks. This shows the universal ability of the process to be adopted as per availability of local feedstock. In this study, a single-step second generation heterogeneous-catalyzed process is developed to produce biodiesel from multi-feedstocks. Due to an increase in the commercial use of biodiesel and biodiesel blends, both ASTM D6751 and EN 14214 include the acid number (AN) as an important quality parameter. Currently, ASTM D974 and D664 analytical methods for acid number analysis of biodiesel are time consuming, expensive, and environmentally not friendly. Therefore, ASTM D974 has been modified and a green analytical method has been developed. This extensive study has demonstrated that this new method is a reliable method for the determination of AN and could be used for establishing the specifications of AN for biodiesel and biodiesel blends ranging from B1 to B20 in quality standards. The ASTM reference standard method D664, has major problems such as the use of excess toxic solvents, large sample size, mediocre reproducibility, tedious process for cleaning electrodes, and relatively long analysis time. Therefore, a new proposed method based on green chemistry approaches, has been developed to determine the acid number of biodiesel and biodiesel blends using small sample size and reduced toxic titration solvent. This proposed green analytical method could be used for the determination of AN of biodiesel and biodiesel blends in R&D as well as industrial quality control laboratories as a simple, time-efficient, cost effective and environmentally friendly method.

Electrospray ionization mass spectrometry (ESI-MS) is well-established in the detection of large fragile organic molecules such as polymers, peptides and proteins. The study of catalysis by transition metal complexes is complicated by difficulties including ligand lability, complex neutrality and air- and moisture-sensitivity. This work is focused on establishing methods to solve these problems and to apply them to well-understood systems in order to establish credibility before applying them to new systems. Attempts to synthesize a 2,2’-bipyridine (bipy)-type ligand designed to have proton sponge-like properties after binding to a metal are presented. The synthesis of 3,3’-N,N’-bis(dimethylamino)-2,2’-bipyridine was stymied by the formation of two strong intramolecular hydrogen bonds, which are clearly evident in the X-ray crystal structure of the isolated dimethylated 3,3’-bis(methylamino)-2,2’-bipyridine. A simple, one step synthesis of a charge-tagged phosphine from commercially available precursors was developed. Monoalkylation of bisphosphines is a highly convenient approach to such ligands, avoiding the multi-step routes demanded for phosphine/ammonium ligands. 4-diphenylphosphino-1-benzyldiphenylphosphonium-butane tetrafluoroborate was used for the investigation of hydrogenation of olefins by RhCl(PPh3)3 (Wilkinson’s catalyst) by ESI-MS. The results obtained by ESI-MS and ESI-MS/MS on the speciation of the reaction as well as the potential reactivity of select species are in agreement with results obtained by traditional techniques. This work serves as a proof of principle that the methodology employed in our lab is suited to these investigations. The same ligand was used to examine the poorly understood dehydrocoupling of di(n-hexyl)silane by the same catalyst. Continuous monitoring of the reaction over 48 minutes added the time dimension to the data, and insight into the dynamics of the reaction was obtained. Key intermediates were observed, along with decomposition products and circumstantial evidence supporting the formation of a silylene intermediate was also obtained. Lastly, some collaborative work is presented in which some of the techniques and methods developed in our laboratory were applied to problems of interest to other scientists. The formation of a heteronuclear ruthenium-gold cluster is monitored by ESI-MS and further analyzed by ESI-MS/MS. The characteristics that affect the surface activity of an ion are discussed and solutions of a dication with two different anions are examined. Biologically active ruthenium trimers were studied by EDESI-MS/MS, and their fragmentation behaviour shown to be analogous to their properties as CO-releasing molecules. / Graduate

The development of systems capable of catalysing the reduction of unsaturated bonds with very high selectivities is one of the greatest successes of asymmetric catalysis. The mechanism by which rhodium complexes catalyse alkene hydrogenation has been effectively established through a combination of kinetic studies and isolation and characterisation of the intermediates in solution. It was hoped to elucidate the corresponding ruthenium catalysed mechanism using similar techniques. Following the synthesis of a selection of ruthenium catalysts, their activity towards the reduction of a selection of dehydroamino acid derivatives at ambient temperature and pressure was investigated. Having successfully tested out the activity of these catalysts, NMR studies were initiated in order to observe and characterise intermediates in the catalytic cycle. Considerable effort was put into the NMR studies, the systems were looked at under both argon and hydrogen, but although some substrate containing species were observed, it was found to be effectively impossible to break into the catalytic cycle and observe intermediate species using NMR techniques. Electrospray mass spectrometry investigations yielded more successful results, though still no hydrogen containing intermediates were observed. However, it was possible to make a detailed kinetic study of several ruthenium catalyst / substrate systems by looking at the dependence of reaction rate on classic variables such as hydrogen pressure, catalyst concentration and substrate concentration. The combined results of electrospray experiments, kinetic analyses and kinetic modelling using computer packages enabled a possible mechanistic pathway to be proposed.

Batch catalytic and high pressure infra-red studies of catalytic systems have provided detailed information about the homogeneous rhodium-chloride catalysed hydrocarbonylation of ethene to form propanoic acid in CH(_3)COOH/c.HC1 at 180ºC and 60 bar pressure. [Rh(CO)(_2)Cl(_2)]- was shown to be an active catalyst for this process. Tin(ll) chloride as a co-catalyst was shown to have an effect on the rate of propanoic acid production for a rhodium-chloride catalytic process, but a clear promotional effect was only observed for systems employing a Sn:Rh molar ratio of 2: 1. Sn:Rh molar ratios higher than 2: 1 lead to a decrease in the selectivity for propanoic acid, while those lower than 2:1 result in catalytic activity consistent with [Rh(CO)(_2)Cl(_2)]- being an active species. The reactions of rhodium(I) carbonyl chlorides with tin(II) chlorides were carried out at atmospheric pressure to investigate the reaction chemistry between species present in the catalytic process. [Rh(CO)(_2)Cl(_2)]- and Rh(_2)(CO)(_4)Cl(_2) react with SnCl(_2) and SnCl(_3)- in both THF and CH(_2)Cl(_2) to form Rh(I)-CO-SnCl(_3) complexes. Infra-red and (^119)Sn NMR data identified the 5-coordinate complex [Rh(CO)(_2)(SnCl(_3)) (_3)](^2-)- as the favoured species formed in solution. Its crystal structure is reported. However, it appears to be related by a series of facile reactions, involving dissociation of SnCl(_3)(^-)- and CO groups, to several other 4 and 5-coordinate Rh(I)-CO-SnCl(-3) complexes. [Rh(CO)(SnCl(_3))(_4)](^3-), [Rh(CO)(SnCl(_3))(_2)Cl](^2-), and [Rh(CO)(_2)(SnCl(_3))X](^-) (X = Cl(^-) or SnCl(_3)(^-)) have been isolated from solution, often as mixtures along with [Rh(CO)(_2)(SnCl(_3))(_3)](^2-). Spectroscopic and X-ray crystallographic data indicated that SnCl(_3)(^-)- is a significant π- tacceptor ligand, thus explaining its ability to form 5-coordinate 18-electron rhodium(I) complexes. The effect of tin(II) chloride on the rhodium-chloride catalytic reaction is attributed to changes in π-acceptor and trans effect properties when SnC1(_3)(^-)- replaces chloride ligand(s). High pressure infra-red studies are consistent with both [Rh(CO)(_2)Cl(_2)](^-) and a Rh(I)CO- SnCl(_3) complex being catalytically active in a rhodium-tin-chloride system, and the carbonyl absorptions observed are consistent with [Rh(CO)(SnCl(_3))(_4)](^3-), [Rh(C0h(SnC(_3))(_3)](^2-) and [Rh(CO)(SnCl(_3))(_2)Cl](^2-) as catalytic precursors. The general predominance of [Rh(CO)(_2)(SnC1(_3))(_3)](^2-) in solution at atmospheric pressure and room temperature, suggests that it may be the favoured catalytic precursor, undergoing conversion to a catalytically active 16-electron Rh(I)-SnC1(_3) complex such as [Rh(CO)(_2)(SnCl(_3))X]- (X = Cl(^-) SnCl(_3)(^-)) via dissociation of SnCl(_3)-.

The work detailed in this thesis is mainly concerned with the carbonylation of fatty acid derivatives, using carbon monoxide atmospheres in the presence of a transition metal. The two systems under study were the conversion of oleonitrile to a cyano-ester using a cobalt catalyst, and formation of isocyanates from amines in the presence of a palladium salt. The objectives of each study were: (i) to assess the influence of physical conditions on the reaction (i.e. pressure, time and temperature);(ii) to examine the effect of various additives on the system (i.e. phosphines, iodides and bases); and (iii) to identify any catalytic species observed under reaction conditions.Three major techniques were employed in each study: autoclave reactions, high pressure infra-red studies and atmospheric pressure nitrogen-line chemistry. The proposed underlying reaction mechanism was examined critically for each system, comparisons being drawn between the postulated catalytic species and those actually observed by high pressure infra-red spectroscopy. The chemical properties of the proposed catalytic intermediates are discussed in relation to the effect of co-reactants on the system. In the case of the carbonylation of oleonitrile the high pressure infra-red studies are consistent with the proposed reaction mechanism based upon the acyl complex RCOCo(CO)(_4). Although the infra-red study on the carbonylation of amines did not reveal any definite information, the results of other experiments were found to be consistent with a system based upon a carboxamido species L(_2)Pd(Cl)(CONRR').

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A range of air- and moisture-stable phosphonium salts was prepared. Compounds were isolated in high yield and fully characterized. The properties of these compounds and the nature of their formation were explored. The phosphonium salts react with base to give phosphino-aldehydes which are important building blocks in the synthesis of PNNP ligands. The condensation reaction between phosphino-aldehydes and a diamine usually employed for the preparation of PNNP ligands was not applicable to the phosphino-aldehydes derived from these phosphonium salts as a result of the high reactivity of the nucleophilic phosphorus causing uncontrollable side-reaction. In order to resolve this problem, a template reaction with iron(II) Lewis acid was used to suppress the reactivity of the phosphorus via coordination. The reaction was successful and gave rise to bis-tridentate complexes with PNN ligands ([Fe(Ph2PCH2CH=N---NH2)2][BPh4]2, where N---NH2 depends on diamine used) as the kinetic product and to desired tetradentate complexes with PNNP ligands (trans-[Fe(Ph2PCH2CH=N---N=CHCH2PPh2)(CH3CN)2][BPh4]2, where N---N depends on diamine used) as a thermodynamic product of the reaction. The reaction appeared to be very general; complexes iii with various diamines incorporated in the ligand backbone were prepared in high yield and fully characterized. Mono-carbonylation reaction of the complexes containing tetradentate PNNP ligands resulted in the formation of the precatalysts with a general formula (trans-[Fe(Ph2PCH2CH=N---N=CHCH2PPh2)(CO)(Br)][BPh4]. These precatalysts give active (TOF up to 28000 h-1) and enantioselective (up to 95 % ee) catalytic systems for the ATH of ketones when activated with base in a solution of 2-propanol as the reducing agent. On the basis of a kinetic study and other evidence, we propose a mechanism of activation and operation of the catalytic system involving the precatalyst trans-[Fe(CO)(Br)(Ph2CH2CH=N-((S,S)-C(Ph)H-C(Ph)H)-N=CHCH2PPh2)][BPh4] and acetophenone as a model substrate. We determined that the activation of the precatalyst to the active species involves the stereoselective reduction of one imine group of the ligand, since when the active species are quenched with acid, the complex trans-[Fe(CO)(Cl)(Ph2CH2CH-(H)N-((S,S)-C(Ph)H-C(Ph)H)-N=CHCH2PPh2)][BPh4] containing amine and imine functionalities in the backbone is produced.