h1

h2

h3

h4

h5
h6
% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@PHDTHESIS{Wiesenthal:964181,
      author       = {Wiesenthal, Jan},
      othercontributors = {Klankermayer, Jürgen and Leitner, Walter},
      title        = {{S}ynthesis of cyclic acetals utilizing homogeneous and
                      immobilized transition metal catalysts},
      school       = {RWTH Aachen University},
      type         = {Dissertation},
      address      = {Aachen},
      publisher    = {RWTH Aachen University},
      reportid     = {RWTH-2023-08154},
      pages        = {1 Online-Ressource : Illustrationen, Diagramme},
      year         = {2023},
      note         = {Veröffentlicht auf dem Publikationsserver der RWTH Aachen
                      University; Dissertation, RWTH Aachen University, 2023},
      abstract     = {The transition to greenhouse gas neutrality represents a
                      key challenge for the chemical Industry. In addition to more
                      efficient processes and energy generation with lower CO2
                      emissions, the use of renewable resources is becoming
                      increasingly important.This work used tailored catalysts to
                      synthesize various cyclic acetals from biomass, CO2, and
                      hydrogen. The versatile acetal products can be used as
                      renewable monomers, solvents, intermediates, and fuels. In
                      the first part, a homogeneous ruthenium-catalyst combined
                      with a Lewis acid was used as the catalytic system to
                      synthesize acetals from biogenic feedstock. The substrates
                      were directly obtained from a fermentation process and
                      converted to 4,5-diethyl-1,3-dioxolane and
                      4,5-dipropyl-1,3-dioxolane using CO2 or formic acid. After
                      producing the acetals on a larger scale, initial combustion
                      properties were determined to evaluate their feasibility as
                      bio-hybrid fuels. In the next step, the 3d metal cobalt was
                      tested as catalytic metal. Cobalt was capable of catalyzing
                      the synthesis of cyclic acetal and promising results were
                      obtained by tailoring the triphos ligand. In detail by
                      substituting the phenyl moieties at the phosphorous with 3,5
                      dimethylphenyl an increase in activity could be observed.
                      For future application of the catalyst system continuous
                      processes, the immobilization of the molecular catalysts is
                      a key factor. Three ligands, vinylSi-triphos,
                      triethoxysilyltriphos, and, triphos-OH, were synthesized,
                      having functional groups allowing immobilization. All
                      ligands are capable of forming the corresponding
                      [Ru(ligand)(tmm)] complex. Using
                      [Ru(triethoxysilyltriphos)(tmm)] immobilized on SBA, cyclic
                      acetals were successfully synthesized in batch and
                      continuous settings. In the next step, a styrene moiety was
                      added to the triphos-OH ligand and via radical
                      copolymerization the triphos was immobilized within a
                      polystyrene polymer. In first test reactions, this solid
                      catalyst showed activity in the synthesis of 1,3-dioxane
                      from 1,3-propanediol, CO2 and H2.},
      cin          = {154310 / 150000},
      ddc          = {540},
      cid          = {$I:(DE-82)154310_20190725$ / $I:(DE-82)150000_20140620$},
      pnm          = {DFG project 390919832 - EXC 2186: Das Fuel Science Center
                      – Adaptive Umwandlungssysteme für erneuerbare Energie-
                      und Kohlenstoffquellen (390919832) / BMBF 03SF0566P0 -
                      Verbundvorhaben NAMOSYN (BMBF-03SF0566P0)},
      pid          = {G:(GEPRIS)390919832 / G:(DE-82)BMBF-03SF0566P0},
      typ          = {PUB:(DE-HGF)11},
      doi          = {10.18154/RWTH-2023-08154},
      url          = {https://publications.rwth-aachen.de/record/964181},
}