Hasan Mehdi, Róbert Tuba, László T Mika, Andrea Bodor, Kornél Torkos, István T Horváth
2006. 01. 01.
Abstract
The sustainability of human civilization primarily depends on whether the energy requirements of its increasing population can be satisfied in the future. While the establishment of the exact date of the depletion of fossil fuels seems difficult, skyrocketing oil and gas prices could come much earlier than 2050, as predicted by several studies. 1 Efficient conversion of solar energy to electricity could open the way to the production of increasing amounts of hydrogen and finally to the development of a hydrogen economy. 1 Of course, the increasing population will demand increasingly larger volumes of carbon-based consumer products. Carbon dioxide is the simplest renewable carbon source, and there are several studies on the hydrogenation of CO2. 2 Since there is no effective direct CO2-based process known to produce large amounts of organic chemicals, nature can help to convert CO2 to biomass, which could serve as the renewable carbon resource. The hydrogenation of carbohydrates could be one of the approaches to produce key carbon-based intermediates. 3 If the currently forecasted transition to a hydrogen economy materializes in the coming decades, 1 hydrogen would be available in large quantities at reasonable prices for the conversion of carbohydrates to a variety of industrial chemical products, including oxygenates or even hydrocarbons such as hexanes and pentanes. The latter could truly be considered as a “renewable oil,” ready to be used by existing technologies.The acid-catalyzed dehydration of carbohydrates giving 5-hydroxymethylfurfural4 (Figure 4.1) and levulinic acid5 (Figure 4.2) is one of the most studied and used …
Abstract
Combinatorial chemistry is a high throughput experimental technique that has significantly changed the drug discovery process in the pharmaceutical industry and become common practice for drug research. Combinatorial synthesis and rapid screening techniques have been applied to the development of homogeneous catalysts and for the optimization of reaction conditions. In contrast to classical experimental design, well‐designed high throughput screening systems can test more catalysts a week than was previously done in a year. This could lead to significant savings in research and development costs. This article provides a survey of the most frequently used combinatorial methods and screening systems applied in homogeneous catalysts discovery. Several examples are presented on the identification of most effective homogeneous catalysts for hydrogenation, hydrosilylation, cyclopropanation …
Róbert Tuba
2024. 03. 22. DSc thesis (in Hungarian) - Thesis (Doctor of the Hung. Acad. of Sci.)
Abstract
A fenntartható katalízis alkalmazása kulcsfontosságú napjaink környezetbarát kémiai technológiáiban. Becslések szerint a kereskedelmi forgalomban levő vegyi anyagok 90%-át részben vagy egészben valamilyen katalitikus reakcióval állítják elő. A kortárs katalitikus kémiai eljárások fejlesztésének számos kihívásnak kell megfelelnie. Elvárható, hogy az új folyamatok alacsony katalizátor koncentráció mellett, zöld oldószerben mutassanak nagy aktivitást. Ezen felül egyre nagyobb hangsúlyt kap a természetes eredetű (megújuló) nyersanyagkeverékek katalitikus értéknövelő átalakítása is. Az olefinek metatézise az elmúlt ötven évben felfedezett új fémorganikus eljárások egyike, amely új alkalmazási lehetőségeket nyitott meg az innovatív anyagok, petrolkémia és gyógyszeripari termékek előállítása területén. Alkalmazása fenntarthatósági szempontból rendkívül előnyös a nagy atomhatékonyság és enyhe reakciókörülmény-igénye miatt. A disszertációban bemutatott kutatómunka olyan, ruténiumalapú metatéziskatalizátor-rendszerek fejlesztésére és alkalmazására összpontosít, amelyek lehetőséget teremtenek fentartható kémiai folyamatok megvalósítására.
Márton Nagyházi
2022. 02. 23. PhD thesis - George Andrew Olah Doctoral School, Budapest University of Technology and Economics (BME)
Abstract
Ligand development is a useful tool to fine-tune transition-metal complex-
based catalyst systems. In the last few decades, hypovalent carbon compounds,
carbenes have also emerged as a possible ligand class, widely exceeding their
principled significance.
In the present work, a systematic investigation of the ligand developments is
presented. By modifying recently discovered cyclic (alkyl)(amino) carbene ligands,
novel catalyst systems have been developed. Two different new types of modified
carbene ligands have been prepared, and their transition metal complexes (ruthenium
and palladium) were used as catalysts in four different catalytic reactions.
Tertiary and quaternary amine-substituted CAAC-Ru systems have shown
activity in olefin metathesis in protic media and ammonia borane hydrolytic
dehydrogenation; while amine- and alkyl group-modified BICAAC-Ru systems have
been found to be exceptional latent catalysts at isomerization-metathesis (ISOMET) of
long-chain olefins, and BICAAC-pyridine-Pd complexes have presented catalytic
activity in Mizoroki-Heck cross-coupling reaction.
Gábor Turczel
2020. 09. 04. PhD thesis - George Andrew Olah Doctoral School, Budapest University of Technology and Economics (BME)
Abstract
The aim of this work is the valorization of low value conjugated feedstock via olefin
metathesis reaction. Naturally occurring, non-edible conjugated fatty acids and their
derivatives are excellent candidates for such feedstock. Nature is also abundant in non-
conjugated polyenes, which could be readily converted to a mixture of conjugated isomers
by catalytic isomerization and utilized in metathesis reaction. These renewable materials can
be considered as a potential sustainable feedstock for polyurethane and polyester monomer
synthesis. Conjugated petrochemical side-products were also investigated as potential raw
materials. The key objective is the utilization of conjugated systems as resource of building
blocks for the synthesis of high-value chemicals. In this work, Grubbs metathesis catalyst systems were employed to convert the =CH-CH= unit of the conjugated starting materials into high-value chemicals having potential industrial applications.