Novel 1,4-chiral diamine ligand possessing a trans-9,10-dihydro-9,10-ethanoanthracene backbone was synthesized. The synthetic plan involves first LiAlH4 reduction of the Diels-Alder adduct obtained by reaction of dimenthyl fumarate and anthracene, which is followed by reacting the corresponding alcohol and subsequent attachment of mesylate and triflate units to get good leaving groups which are available substances for introducing nitrogen units via SN2 type reactions. Consequently, by using dimesyl ester and ditriflate esters five catalysts 27, 29, 30, 33 and 38 were synthesized. The first four catalysts 27, 29, 30 and 33 were used in transfer hydrogenation reactions with transition metal whereas catalyst 38 used as an organocatalyst in direct aldol reaction between acetone and p-nitrobenzaldehyde.

Hydrogenation is one of the most applied techniques in the fats and oils industry to produce wide range of hardened fats with different physical and chemical properties. Each different combination of hydrogenation conditions serves products of different rheological and micro-structural properties. Therefore, the purpose of this study is to examine the effect of different industrially available catalysts on rheological and micro-structural properties of hydrogenated fats. Three different catalysts were used at two different concentrations to hydrogenate soybean oil. Two nickel based (Nysosel 222 and SP 10) and one palladium based (Pd/Al2O3) catalyst were employed. Each oil sample was hydrogenated for 20, 40, 60, 80 and 100 minutes of time intervals, under 165 &ordm / C temperature, 2 bar H2 pressure and 500 rpm stirring rate. Resulting hardened fat samples were analysed in terms of rheological and microstructural properties. The outcomes of rheological and micro-structural analyses had a strong resemblence with the fatty acid distributions, solid fat contents, slip melting points and iodine values of the samples. The most selective catalyst was SP10, with the products of the highest trans fatty acid concent and more solid-like / where the least selective one was Pd/A with lowest trans fatty acid content and least solid-like. Crystal number and properties, the behaviours of storage and loss moduli were in correlation with trans fatty acid content of the samples. Also the moduli had a considerable parallelity with solid fat contents.

Abstract The reactivity and bonding of allyl groups (C3H5) on a Ag(111) surface have been investigated under ultrahigh vacuum conditions by temperature-programmed reaction/desorption (TPR/D) and reflection-adsorption infrared spectroscopy (RAIRS). The atomically clean surface was achieved by Ar+ sputtering and verified by AES. The surface crystallinity was assured by LEED. Surface -bound allyl groups were generated by dissociative adsorption of allyl halides. Our study shows that the C-X (X= I or Cl) bond can be ruptured below 200K to render adsorbed allyl species. Upon further heating, three gas-phase products were detected at ~280 K, 295 K and 320 K in the TPR/D spectra, which are attributed to 1,5-hexadiene, allene, and propene, respectively. These results suggest that allyl undergoes

The thesis entitled Cholic Acid Bused New Chiral Auxiliaries: Development And Applications has been divided into three chapters. Chapter-I describes the synthesis of chiral auxiliaries (1.3) from cholic acid and Diets-Alder reactions on the corresponding a,B- unsaturated ester derivatives. Chapter-I1 deals with the asymmetric dihydroxylation of a,B unsaturated esters of steroidal alcohols (1-3). Chapter-HI describes asymmetric hydride reduction, hydrogenation and allylation of a-keto esters of cholic acid derivatives (1-3).

As an important chemical raw material, alcohols can be used as fuels, solvents and chemical feedstocks to produce a variety of downstream products. With limited fossil fuel resources, alcohol synthesis from syngas reactions can be a potential alternative to the traditional petroleum based alcohol synthesis. Among many catalysts active for syngas to alcohol processes, alkali promoted Mo2C has shown promising performance. More interestingly, the alkali promoter was found to play an important role in shifting the reaction selectivity from hydrocarbons to alcohols. However, limited understanding of the mechanism of this alkali promoter effect is available due to the complexity of syngas reaction mechanism and low content of alkali added to the catalysts. In this thesis, we performed a comprehensive investigation of the alkali promoter effect with density functional theory (DFT) calculations as our primary tool. We first examine various Mo2C surfaces to determine a representative surface structure active to alkali adsorption. On this particular surface, we develop a syngas reaction network including relevant reaction mechanisms proposed in previous literature. With energetics derived from DFT calculations and a BEP relation, we predict the syngas reaction selectivity and find it to be in excellent agreement with experimental results. The dominant reaction mechanism and selectivity determining steps are determined from sensitivity analysis. We also propose a formation mechanism of alkali promoters on Mo2C catalysts that shows consistency between experimental IR and DFT computed vibrational frequencies. Finally, the effect of alkali promoters on the selectivity determining steps for syngas reactions are investigated from DFT calculations and charge analysis. We are able to rationalize the role of alkali promoters in shifting the reaction selectivity from hydrocarbons to alcohols on Mo2C catalysts.

The focus of my graduate research in the Krische group has been the development of catalytic carbon-carbon bond forming reactions with an emphasis on controlling diastereo- and enatio-selectivity in transfer hydrogenative couplings. The broad goal of our research program has been the development and implementation of efficient green methods for carbonyl addition employing [pi]-unsaturates as surrogates to preformed organometallic reagents, thus enabling byproduct free variants of traditional carbanion chemistry. This dissertation shows the new reactions that I have developed toward this goal. These reactions includes new metal catalyzed approaches for carbonyl crotylation, aminoallylation, and vinylogous reformatsky aldol reactions. / text

Under the conditions of transfer hydrogenation utilizing chromatographically purified ortho-cyclometallated iridium C,O-benzoate precatalysts, enantioselective carbonyl crotylation and methallylation can be performed in the absence of stoichiometric metallic reagents and stoichiometric chiral modifiers. In the case of carbonyl crotylation, use of a preformed precatalyst rather than an in situ generated catalyst results in lower reaction temperatures, providing generally higher diastereoselectivity and yields. By utilizing a more reactive leaving group in chloride over acetate on our methallyl donor, the inherently shorter lifetime of the olefin π-complex is compensated for, giving our group’s first report of reactivity utilizing 1,1-disubstituted allyl donors. / text

At the threshold of the 21st centry, a new set of challenges is defined by the need to develop sustainable means of preparing chemical commodities demanded by society. Hence, such concepts as atom economy, step economy, and 'green chemistry' have become the requirements for the development of synthetic reactions. Hydrogenation is one of the most powerful catalytic methods which successfully satisfy the stated requirements of modern chemistry. Accordingly, catalytic hydrogenation has been tremendously utilized in industrial settings. The profound impact of hydrogenation portended a powerful approach to reductive carbon-carbon bond formation under hydrogenation conditions, resulting in the discovery of the Fischer-Tropsch process and hydroformylation. However, since this discovery, processes have restricted to the incorporation of a single carbon monoxide unit. Even though there are a few seminal contributions, systematic efforts toward the development of hydrogen-mediated carboncarbon bond forming processes beyond hydroformylation have been absent from the literature. In an exciting advance, the Krische group has shown that it is possible to reductively couple two or more organic molecules simply through their exposure to gaseous hydrogen in the presence of a metal catalyst. This finding has led to the development of a broad, new family of hydrogen-mediated C-C bond formation. Herein, related to hydrogen-mediated C-C bond formation, the overview of metal catalyzed intermolecular reductive coupling in the presence of reducing agents such as borane, silane, alane, metal, and hydrogen is presented. Chapter 2 describes systematic approaches to the development of hydrogen-mediated C-C bond formation and successful preliminary results achieved by our research group. Chapters 3 and 4 will describe the further extension of these hydrogen-mediated C-C bond formations including (1) hydrogen-mediated reductive couplings of conjugated alkynes with iminoacetates, (2) hydrogen-mediated reductive couplings of 1,3-enynes with [alpha]-ketoesters, and (3) hydrogen-mediated multicomponent reductive couplings. The development of catalytic systems for the nucleophilic activation of enones using phosphine catalysts has received attractive attention. Recently, an intramolecular variant of the Rauhut-Currier reaction was developed in our lab. To further extend nucleophilic phosphine catalysis, we have sought to develop new catalytic methodology via phosphine conjugate addition. Chapter 5 describes two new methodologies related to their area: (1) catalytic cycloallylation via nucleophilic phosphine catalysis and (2) allylic amination of Morita-Baylis-Hillman acetates. / text

Hydrogen gas is the cleanest and most cost-effective reductant available to mankind, and the use of hydrogen gas in catalytic hydrogenation reactions is one of the oldest and most utilized organic reactions. Although catalytic hydrogenation has been practiced in industry on enormous scale, the use of hydrogen gas as a terminal reductant in C-C bond forming reactions has been limited to processes involving the migratory insertion of carbon monoxide such as: alkene hydroformylation and the Fischer-Tropsch reaction. A significant advance to the field of synthetic organic chemistry would be the expansion of C-C bond forming reactions beyond reductive coupling via carbon monoxide insertion. Herein, related metal catalyzed reductive couplings to [alpha],[beta]-unsaturated compounds in the presence of reducing agents such as: silane, borane, and hydrogen are reviewed. The following chapters discuss the development of hydrogen-mediated reductive aldol and Mannich reactions. The results from this body of work clearly demonstrate that hydrogen-mediated C-C bond forming reactions are emerging as a powerful tool for synthetic chemists.

Η Υδρογόνωση του Διοξειδίου του Άνθρακα έχει προσελκύσει διεθνώς το ενδιαφέρον της επιστημονικής κοινότητας τόσο ως πιθανή πηγή ανανεώσιμων καυσίμων όσο και ως μέσο μείωσης των εκπομπών του CO2. Στην παρούσα μελέτη χρησιμοποιείται το φαινόμενο της Ηλεκτροχημικής Ενίσχυσης (Η/Ε) της κατάλυσης (EPOC) ή μη- Φαρανταϊκή Ηλεκτροχημική Τροποποίηση της καταλυτικής ενεργότητας (φαινόμενο NEMCA) για την ενίσχυση του ρυθμού και της εκλεκτικότητας της υδρογόνωσης του CO2 σε καταλύτη ρουθηνίου (Ru) υποστηριζόμενου σε πρωτονιακό αγωγό ΒZY. Αρχικά γίνεται μια Εισαγωγή για το Διοξείδιο του Άνθρακα στην οποία και εξηγείται η αναγκαιότητα της περεταίρω μελέτης της αντίδρασης υδρογόνωσης του CO2. Στο Κεφάλαιο 1 γίνεται μια εκτεταμένη αναφορά στους στερεούς ηλεκτρολύτες, με ιδιαίτερη έμφαση στους στερεούς ηλεκτρολύτες πρωτονιακής αγωγιμότητας. Στη συνέχεια στο δεύτερο Κεφάλαιο περιγράφεται το φαινόμενο της Ηλεκτροχημικής Ενίσχυσης της κατάλυσης, γίνεται μια αναφορά των μελετών Η/Ε που έχουν προηγηθεί και παρατίθενται οι κανόνες που διέπουν το συγκεκριμένο φαινόμενο. Στο τρίτο Κεφάλαιο γίνεται βιβλιογραφική ανασκόπηση της συγκεκριμένης αντίδρασης τόσο καταλυτικά όσο και ηλεκτροκαταλυτικά. Στο Κεφάλαιο 4 ακολουθεί η περιγραφή της πειραματικής διάταξης καθώς και ο χαρακτηρισμός του καταλύτη αλλά και τα πειράματα χαρακτηρισμού του ηλεκτρολύτη. Έπειτα, στο Κεφάλαιο 5 παρουσιάζονται τα πειραματικά αποτελέσματα (θερμοκρασιακά, κινητικά, δυναμικής απόκρισης κτλ.), καθώς και μια ποιοτική ανάλυση των παραπάνω αποτελεσμάτων. Και τέλος παρατίθενται τα συνολικά συμπεράσματα της συγκεκριμένης μελέτης. / The Hydrogenation of Carbon Dioxide has attracted international interest in the scientific community as a potential source of renewable fuels and as a means of reducing CO2 emissions. In this study the phenomenon of Electrochemical Promotion of Catalysis (EPOC) or non-Faradaic Electrochemical Modification of Catalytic Activity (NEMCA) is used in order to enhance the rate and selectivity of this reaction on a Ruthenium (Ru) catalyst deposited on a proton conductor (BZY). The electrochemical promotion of the hydrogenation of CO2 on polycrystalline Ru deposited on a BZY (BaZr0.85Y0.15O3 + 1wt% NiO), a proton conductor in wet atmospheres, was investigated at temperatures 250 to 450oC and atmospheric pressure. Methane and CO were the only detectable products. It was found that the selectivity to CH4 is very significantly enhanced by proton removal from the catalyst via electrochemically controlled spillover of atomic H from the catalyst surface to the proton-conducting support. The apparent Faradaic efficiency of the process takes values up to 500 and depends strongly on the porous Ru catalyst film thickness. The results strongly suggest that the observed strong promotional effect is due to the formation and surface migration of a promoting formate anion generated via potential controlled disproportionation of formic acid adsorbed at the catalyst-proton conducting support interface. This is the first successful electrochemical promotion study of a hydrogenation reaction at temperatures as low as 250oC. There is an up to fourfold enhancement in catalytic rate of CH4 formation with concomitant 50% suppression of the CO formation rate which proceeds in a parallel route.