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Zhang, W. (author), Gacs, Jenő (author), Arends, I.W.C.E. (author), Hollmann, F. (author)
The aerobic organocatalytic oxidation of alcohols was achieved by using water-soluble sodium anthraquinone sulfonate. Under visible-light activation, this catalyst mediated the aerobic oxidation of alcohols to aldehydes and ketones. The photo-oxyfunctionalization of alkanes was also possible under these conditions.
journal article 2017
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Zhang, W. (author), Bariotaki,, A. (author), Smonou, I. (author), Hollmann, F. (author)
Carbon-nanodot-doped g-C3N4 is used as a photocatalyst to promote the aerobic oxidation of alcohols and oxyfunctionalisation of activated hydrocarbons. A critical E-factor analysis of the current reaction system reveals its limitations en route to environmentally acceptable oxidation procedures.
journal article 2017
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Zhang, W. (author), Burek, Bastien O. (author), Fernandez Fueyo, E. (author), Alcalde, Miguel (author), Bloh, Jonathan Z. (author), Hollmann, F. (author)
Selective oxyfunctionalizations of inert C−H bonds can be achieved under mild conditions by using peroxygenases. This approach, however, suffers from the poor robustness of these enzymes in the presence of hydrogen peroxide as the stoichiometric oxidant. Herein, we demonstrate that inorganic photocatalysts such as gold–titanium dioxide...
journal article 2017
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Dong, J. (author), Fernandez Fueyo, E. (author), Hollmann, F. (author), Paul, C.E. (author), Pesic, M. (author), Schmidt, S. (author), Wang, Yonghua (author), Younes, S.H.H. (author), Zhang, W. (author)
Oxidation chemistry using enzymes is approaching maturity and practical applicability in organic synthesis. Oxidoreductases (enzymes catalysing redox reactions) enable chemists to perform highly selective and efficient transformations ranging from simple alcohol oxidations to stereoselective halogenations of non‐activated C−H bonds. For many of...
journal article 2018
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Zhang, W. (author), Fernandez Fueyo, E. (author), Ni, Y. (author), van Schie, M.M.C.H. (author), Gacs, Jenö (author), Renirie, R. (author), Wever, Ron (author), Mutti, Francesco G. (author), Rother, Dörte (author), Alcalde, Miguel (author), Hollmann, F. (author)
Peroxygenases offer an attractive means to address challenges in selective oxyfunctionalization chemistry. Despite this, their application in synthetic chemistry remains challenging due to their facile inactivation by the stoichiometric oxidant H<sub>2</sub>O<sub>2</sub>. Often atom-inefficient peroxide generation systems are required, which...
journal article 2018
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Zhang, W. (author), Hollmann, F. (author)
Oxidoreductases have become useful tools in the hands of chemists to perform selective and mild oxidation and reduction reactions. Instead of mimicking native catalytic cycles, generally involving costly and unstable nicotinamide cofactors, more direct, NAD(P)-independent methodologies are being developed. The promise of these approaches not...
journal article 2018
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Zhang, W. (author), Fernandez Fueyo, E. (author), Hollmann, F. (author), Leemans Martin, L. (author), Pesic, M. (author), Wardenga, Rainer (author), Höhne, Matthias (author), Schmidt, S. (author)
In this study, we combined photo-organo redox catalysis and biocatalysis to achieve asymmetric C–H bond functionalization of simple alkane starting materials. The photo-organo catalyst anthraquinone sulfate (SAS) was employed to oxyfunctionalise alkanes to aldehydes and ketones. We coupled this light-driven reaction with asymmetric enzymatic...
journal article 2018
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Huijbers, M.M.E. (author), Zhang, W. (author), Tonin, F. (author), Hollmann, F. (author)
The photoenzymatic decarboxylation of fatty acids to alkanes is proposed as an alternative approach for the synthesis of biodiesel. By using a recently discovered photodecarboxylase from Chlorella variabilis NC64A (CvFAP) we demonstrate the irreversible preparation of alkanes from fatty acids and triglycerides. Several fatty acids and their...
journal article 2018
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Bormann, Sebastian (author), van Schie, M.M.C.H. (author), Pedroso de Almeida, T. (author), Zhang, W. (author), Stöckl, Markus (author), Ulber, Roland (author), Hollmann, F. (author), Holtmann, Dirk (author)
Various enzymes utilize hydrogen peroxide as an oxidant. Such “peroxizymes” are potentially very attractive catalysts for a broad range of oxidation reactions. Most peroxizymes, however, are inactivated by an excess of H<sub>2</sub>O<sub>2</sub>. The electrochemical reduction of oxygen can be used as an in situ generation method for hydrogen...
journal article 2019
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Choi, Da Som (author), Lee, Hojin (author), Tieves, F. (author), Lee, Yang Woo (author), Son, Eun Jin (author), Zhang, W. (author), Shin, Byungha (author), Hollmann, F. (author), Park, Chan Beum (author)
Peroxygenases catalyze selective oxyfunctionalization of hydrocarbons with high conversion efficiencies using H<sub>2</sub>O<sub>2</sub> as a key cosubstrate. Here, we report an unbiased photoelectrochemical (PEC) tandem structure consisting of a FeOOH/BiVO<sub>4</sub> photoanode, a Cu(In,Ga)Se<sub>2</sub> solar absorber, and a graphitic...
journal article 2019
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Zhang, W. (author), Ma, M. (author), Huijbers, M.M.E. (author), Filonenko, G.A. (author), Pidko, E.A. (author), van Schie, M.M.C.H. (author), de Boer, Sabrina (author), Smith, W.A. (author), Hollmann, F. (author)
A recently discovered photodecarboxylase from Chlorella variabilis NC64A ( CvFAP) bears the promise for the efficient and selective synthesis of hydrocarbons from carboxylic acids. CvFAP, however, exhibits a clear preference for long-chain fatty acids thereby limiting its broad applicability. In this contribution, we demonstrate that the...
journal article 2019
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Ma, Yunjian (author), Li, Yongru (author), Ali, Shahid (author), Li, Peilin (author), Zhang, W. (author), Rauch, M.C.R. (author), Willot, S.J. (author), Ribitsch, Doris (author), Hollmann, F. (author)
Natural deep eutectic solvents (NADES) are proposed as alternative solvents for peroxygenase-catalysed oxyfunctionalization reactions. Choline chloride-based NADES are of particular interest as they can serve as solvent, enzyme-stabiliser and sacrificial electron donor for the in situ H<sub>2</sub>O<sub>2</sub> generation. This report...
journal article 2019
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Zhang, Tianyu (author), Ma, Yunjian (author), Tan, Chin Ping (author), Hollmann, F. (author), Wang, Jianrong (author), Yang, Bo (author), Wang, Yonghua (author)
Poor H <sub>2</sub> O <sub>2</sub> -resistance by enzymes is a key bottleneck in the epoxidation process of oil by enzymatic methods. In this study, the stability of three lipases, from Aspergillus oryzae lipase (AOL), Aspergillus fumigatus lipase B (AflB), and marine Janibacter (MAJ1), in the presence of H <sub>2</sub> O <sub>2</sub> was...
journal article 2019
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Tieves, F. (author), Willot, S.J. (author), van Schie, M.M.C.H. (author), Rauch, M.C.R. (author), Younes, S.H.H. (author), Zhang, W. (author), Dong, J. (author), Gomez de Santos, P. (author), Hollmann, F. (author)
An increasing number of biocatalytic oxidation reactions rely on H <sub>2</sub> O <sub>2</sub> as a clean oxidant. The poor robustness of most enzymes towards H <sub>2</sub> O <sub>2</sub> , however, necessitates more efficient systems for in situ H <sub>2</sub> O <sub>2</sub> generation. In analogy to the well-known formate dehydrogenase to...
journal article 2019
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Gacs, Jenő (author), Zhang, W. (author), Knaus, Tanja (author), Mutti, Francesco G. (author), Arends, I.W.C.E. (author), Hollmann, F. (author)
The consecutive photooxidation and reductive amination of various alcohols in a cascade reaction were realized by the combination of a photocatalyst and several enzymes. Whereas the photocatalyst (sodium anthraquinone-2-sulfonate) mediated the light-driven, aerobic oxidation of primary and secondary alcohols, the enzymes (various ω...
journal article 2019
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Ma, Yunjian (author), Li, Peilin (author), Li, Yongru (author), Willot, S.J. (author), Zhang, W. (author), Ribitsch, Doris (author), Choi, Young Hae (author), Verpoorte, Robert (author), Hollmann, F. (author)
The use of natural deep eutectic solvents (NADES) as multifunctional solvents for limonene bioprocessing was reported. NADES were used for the extraction of limonene from orange peel wastes, as solvent for the chemoenzymatic epoxidation of limonene, and as sacrificial electron donor for the in situ generation of H <sub>2</sub> O <sub>2</sub>...
journal article 2019
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Burek, Bastien O. (author), de Boer, Sabrina R. (author), Tieves, F. (author), Zhang, W. (author), van Schie, M.M.C.H. (author), Bormann, Sebastian (author), Alcalde, Miguel (author), Holtmann, Dirk (author), Hollmann, F. (author)
Photoenzymatic cascades can be used for selective oxygenation of C−H-Bonds under mild conditions circumventing the hydrogen peroxide mediated peroxygenase inactivation via in situ H<sub>2</sub>O<sub>2</sub> generation. Here, we report the “on demand” production of hydrogen peroxide via methanol assisted reduction of molecular oxygen using UV...
journal article 2019
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Zhang, Jie (author), Tonin, F. (author), Zhang, W. (author), Hagedoorn, P.L. (author), Mallée, L. (author), Hollmann, F. (author)
We report the use of commercial laundry powder as a biocatalyst for a range of lipase-catalysed reactions including (trans)esterification, ester hydrolysis and chemoenzymatic epoxidation reactions. The enzymatic laundry powder exhibited excellent stability and recyclability, making it a readily available and cheap biocatalyst for chemical...
journal article 2019
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van Schie, M.M.C.H. (author), Zhang, W. (author), Tieves, F. (author), Choi, Da Som (author), Park, Chan Beum (author), Burek, Bastien O. (author), Bloh, Jonathan Z. (author), Arends, I.W.C.E. (author), Paul, C.E. (author), Alcalde, Miguel (author), Hollmann, F. (author)
Peroxygenases are very interesting catalysts for specific oxyfunctionalization chemistry. Instead of relying on complicated electron transport chains, they rely on simple hydrogen peroxide as the stoichiometric oxidant. Their poor robustness against H<sub>2</sub>O<sub>2</sub> can be addressed via in situ generation of H<sub>2</sub>O<sub>2<...
journal article 2019
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Zhang, W. (author), Hollmann, F. (author)
Enzymatic methods for the polymerisation of vinyl monomers are presented and critically discussed. Vinyl monomers can be polymerised initiated by enzyme-catalysed radical formation. The most widely used initiators for this purpose are β-diketo compounds, which can be transformed into the corresponding radicals via peroxidase- or laccase...
book chapter 2019
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