The growing awareness of environmental issues and sustainable development is focused on
obtaining materials from renewable sources. Lignocellulosic biomass represents the most
important renewable source of organic carbon on earth, making it a natural source for the
production of chemicals. In doctoral dissertation, we focused on the utilization of less utilized
components of plant biomass from IAPS (lignin, ferulic acid, and secondary metabolites).
We investigated the oxidative cleavage of double and single C–C bonds, which is an important
reaction for decomposition of complex molecules from biomass, from a synthetic point of
view. Using the oxidant H2O2 and the catalyst V2O5, we developed a method for selective
oxidative cleavage of C–C double bonds. The method allows selective conversion of cinnamic
acid derivatives into benzaldehydes, benzoquinones or benzoic acids. The selectivity of the
reaction depends on the solvent chosen. Derivatives of p-hydroxycinnamic acid were
selectively converted to the corresponding benzaldehydes in DME and to benzoquinones in
TFE. Cinnamic acid and styrene derivatives, which do not have a hydroxyl group at the para
site, were selectively converted to benzoic acids in MeCN. The method allows selective
conversion of ferulic acid to vanillin (91 %) in the presence of 7 eq. of 30 % H2O2 and 5 mol%
catalyst. Oxidative cleavage of single C-C bonds plays an important role in the conversion of
lignin to platform chemicals. A previously developed method based on H2O2/V2O5 was
extended to various types of lignin. We used commercial lignin and real samples of kraft and
organosolv lignin from Japanese knotweed, Staghorn sumac, and spruce. Due to the different
structures of the lignin samples as determined by NMR spectroscopy, oxidative degradation
was studied separately on all three sample types. In DME, commercial lignin and kraft lignin
of spruce were successfully converted to vanillin (yields: 9.9% and 7.6%). Kraft lignin from
Japanese knotweed was successfully depolymerized to a mixture of aromatic products.
IAPS are rich in various structural types of natural dyes, that have been isolated by extraction.
Emodin isolated from Japanese knotweed was chemically modified by introducing various
functional groups through nitration, sulfonation, and halogenation. Chemical modification of
the emodin structure affected its color, binding, and antiviral and antibacterial properties. The
emodin derivatives were photochemically characterized and used as photoredox catalysts for
photoreduction of aryl halides. A Structure-Activity Relationship was performed with the
emodin derivatives for antiviral activity against HCoV-NL63. Iodinated E-3I and brominated
emodin E-2Br showed comparable antiviral activity as Remdesivir, which is already approved
for use in emergency COVID-19 cases. Emodin derivatives were successfully bound to textile
material (wool and polyamide). The functionalized textile material also showed antibacterial
activity against S. aureus. Emodin, IAPS extracts, lignin and PHA were successfully
incorporated into silane-type coatings, enabling the preparation of colored and transparent
hydrophobic coatings for glass and wood.
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