512-85-6Relevant articles and documents
Singlet-Oxygen Generation by Peroxidases and Peroxygenases for Chemoenzymatic Synthesis
Ingenbosch, Kim N.,Quint, Stephan,Dyllick-Brenzinger, Melanie,Wunschik, Dennis S.,Kiebist, Jan,Süss, Philipp,Liebelt, Ute,Zuhse, Ralf,Menyes, Ulf,Scheibner, Katrin,Mayer, Christian,Opwis, Klaus,Gutmann, Jochen S.,Hoffmann-Jacobsen, Kerstin
, p. 398 - 407 (2020/10/09)
Singlet oxygen is a reactive oxygen species undesired in living cells but a rare and valuable reagent in chemical synthesis. We present a fluorescence spectroscopic analysis of the singlet-oxygen formation activity of commercial peroxidases and novel peroxygenases. Singlet-oxygen sensor green (SOSG) is used as fluorogenic singlet oxygen trap. Establishing a kinetic model for the reaction cascade to the fluorescent SOSG endoperoxide permits a kinetic analysis of enzymatic singlet-oxygen formation. All peroxidases and peroxygenases show singlet-oxygen formation. No singlet oxygen activity could be found for any catalase under investigation. Substrate inhibition is observed for all reactive enzymes. The commercial dye-decolorizing peroxidase industrially used for dairy bleaching shows the highest singlet-oxygen activity and the lowest inhibition. This enzyme was immobilized on a textile carrier and successfully applied for a chemical synthesis. Here, ascaridole was synthesized via enzymatically produced singlet oxygen.
Nature inspired singlet oxygen generation to access α-amino carbonyl compounds: Via 1,2-acyl migration
Schilling, Waldemar,Zhang, Yu,Sahoo, Prakash Kumar,Sarkar, Samir Kumar,Gandhi, Sivaraman,Roesky, Herbert W.,Das, Shoubhik
supporting information, p. 379 - 387 (2021/01/28)
We have discovered chlorophyll catalyzed 1,2-acyl migration reactions to achieve α-amino carbonyl compounds directly from the enaminones. In general, singlet oxygen is generated during photosynthesis in the photosystem II center. This singlet oxygen can readily react with the unsaturated double bonds present in biomolecules. This reactivity intrigued us to apply this concept towards unsaturated enaminones and others to achieve highly valuable compounds. Indeed, this photosensitizer is very cheap, commercially available, main group metal based and provided excellent efficiency for singlet oxygen mediated chemistry by achieving high turnover number (TON) > 300 with a high turnover frequency (TOF) of 50 h-1. Finally, a combination of DFT calculations and detailed mechanistic experiments provided the exact role of the photosensitizer and clear insights into the reaction.
COVALENT ORGANIC FRAMEWORKS AND APPLICATIONS AS PHOTOCATALYSTS
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Paragraph 00145; 00162-00164, (2021/05/21)
Described herein are covalent organic frameworks. The covalent organic frameworks have unique structural and physical properties, which lends them to be versatile in a number of different applications and uses. In one aspect, the covalent organic frameworks are composed of a plurality of fused aromatic groups and electron-deficient chromophores. The covalent organic frameworks are useful as photocatalysts in a number of different applications.