Proc Natl Acad Sci U S A
Department of Chemistry, Faculty of Science, Graduate School, Kyushu University 33, Fukuoka 812-8581, Japan.
Published: April 2004
Baeyer-Villiger oxidation of racemic bicyclic cyclobutanones with Zr[bis(salicylidene)ethylenediaminato] (salen) complex 1 as catalyst in the presence of a urea-hydrogen peroxide adduct was found to proceed enantiospecifically. The enantiotopos selection in the oxidation was governed primarily by the Zr(salen) catalyst, although migratory aptitude (methine > methylene > methyl) in Baeyer-Villiger oxidation affected the selection to a varied extent, depending on the substrate structures; one enantiomer of cyclobutanones gave exclusively a normal lactone expected from the migratory aptitude, and the other enantiomer gave an abnormal lactone preferentially, the formation of which is counter to the migratory aptitude. Furthermore, the rates of abnormal lactone formation were found to be faster than those of normal lactone formation in most of the oxidations examined. For example, the enantiomer of racemic bicyclo[3.2.0]heptan-6-one giving an abnormal lactone reacted 2.2 times faster than the other enantiomer giving a normal lactone. To our knowledge, this example of chemocatalytic Baeyer-Villiger oxidation giving an abnormal lactone in preference to a normal lactone has been previously unreported. This unusual behavior is likely to be attributable to strict control of stereoelectronic demand in Baeyer-Villiger oxidation and chiral recognition by complex 1.
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http://dx.doi.org/10.1073/pnas.0306992101 | DOI Listing |
Int J Biol Macromol
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College of Bioscience and Bioengineering, Fuzhou University, Fuzhou 360105, China. Electronic address:
Baeyer-Villiger monooxygenases (BVMOs) can catalyze the asymmetric sulfoxidation to form pharmaceutical prazoles in environmentally friendly approach. In this work, the thermostable BVMO named PockeMO had high sulfoxidation activity towards rabeprazole sulfide to form (R)-rabeprazole but demonstrated significant overoxidation activity to form undesired sulfone by-product. To address this issue, the enzyme was engineered based on the computer assisted comparison for the substrate binding conformations.
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January 2025
Center for Analysis and Synthesis, Department of Chemistry, Lund University, Lund SE 221 00, Sweden.
A diastereospecific synthesis of vicinally substituted 2-oxazolidinones from α,β-unsaturated lactams using -chloroperoxybenzoic acid is reported. Several highly substituted 2-oxazolidinones were obtained in 19-46% yields in a one-pot reaction with complete control over the relative stereochemistry. The proposed reaction sequence consists of a Baeyer-Villiger oxidation, an epoxidation, and a concerted rearrangement.
View Article and Find Full Text PDFPhytochemistry
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School of Food Science and Pharmaceutical Engineering, Testing & Analysis Center, Nanjing Normal University, Nanjing, 210023, China. Electronic address:
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View Article and Find Full Text PDFInorg Chem
December 2024
Henan Key Laboratory of Polyoxometalate Chemistry, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, Henan 475004, P. R. China.
Directed synthesis of high-efficiency visible photoinduced Baeyer-Villiger oxidation catalysts is of primary significance. Here, the isopolymolybdate anion [β-MoO] is for the first time encapsulated with the photosensitive metalloligand [Ru(bpy)(Hdcbpy)] (bpy = 2,2'-bipyridine; Hdcbpy = 2,2'-bipyridine-5,5'-dicarboxylic acid) to synthesize polyoxometalate@metal-organic frameworks, {(CdDMF)[Ru(bpy)(dcbpy)]([β-MoO])}·5DMF (Ru-Mo). The composite photocatalyst Ru-Mo not only has a light absorption of 700 nm but also shortens the photogenerated electron transfer distances and accelerates charge and proton transfer.
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December 2024
Institute of Chemistry, Moldova State University, 2028 Chisinau, Moldova.
The synthesis of tetra- and pentanorlabdane compounds with rearranged cycle B based on commercially available (+)-sclareolide is reported. Desired compounds were prepared from intermediate ketones via Baeyer-Villiger oxidation. The structures of synthesized compounds were confirmed by spectral IR, 1D (H, C, and DEPT), and 2D (H-COSY, H,C-HSQC, H,C-HMBC, H,N-HMBC, NOESY) NMR analyses, mass-spectrometry and single crystal X-rays diffraction.
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