1783-81-9Relevant articles and documents
Modulation of photochemical oxidation of thioethers to sulfoxides or sulfones using an aromatic ketone as the photocatalyst
Zhao, Bin,Hammond, Gerald B.,Xu, Bo
supporting information, (2021/09/13)
We have developed an eco-friendly and chemo-selective photocatalytic synthesis of sulfoxides or sulfones via oxidation of sulfides (thioethers) at ambient temperature using air or O2 as the oxidant. An inexpensive thioxanthone was used as the photocatalyst. Our method offers excellent chemical yields and good functional group tolerance. The hydrogen bonding between hexafluoro-2-propanol (HFIP) and sulfoxides may play an important role in minimizing the over-oxidization of sulfoxides.
Hydroboration reduction reaction of aromatic nitro compounds without transition metal catalysis
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Paragraph 0006; 0033-0036, (2021/07/31)
The invention relates to a hydroboration reduction reaction of aromatic nitro compounds without transition metal catalysis. According to the method, triethyl boron and potassium tert-butoxide are used as catalysts for the first time, and an aromatic nitro compound and pinacol borane which is low in price and easy to obtain can be conveniently catalyzed to be subjected to a hydroboration reduction reaction under mild conditions to prepare aromatic amine products. Compared with a traditional method, the method generally has the advantages that the catalyst is cheap and easy to obtain, operation is convenient, and reaction is safe. The selective hydroboration reduction reaction of the non-transition metal reagent catalyzed aromatic nitro compound and pinacol borane is realized for the first time, and a practical new reaction strategy is provided for laboratory preparation or industrial production of aromatic amine products.
Identification of MsrA homologues for the preparation of (R)-sulfoxides at high substrate concentrations
Yang, Jiawei,Wen, Yuanmei,Peng, Liaotian,Chan, Yu,Cheng, Xiaoling,Chen, Yongzheng
, p. 3381 - 3388 (2019/04/01)
Here we report a methionine sulfoxide reductase A (MsrA) homologue with extremely high substrate tolerance and a wide substrate scope for the biocatalytic preparation of enantiopure sulfoxides. This MsrA homologue which was obtained from Pseudomonas alcaliphila (named paMsrA) showed good activity and enantioselectivity towards a series of aryl methyl/ethyl sulfoxides 1a-1k, with electron-withdrawing or electron-donating substituents at the aromatic ring. Chiral sulfoxides in the R configuration were prepared with approximately 50% of yield and up to 99% enantiomeric excess through the asymmetric reductive resolution of racemic sulfoxide catalyzed by the recombinant paMsrA protein. More importantly, kinetic resolution has been successfully accomplished with high enantioselectivity (E > 200) at initial substrate concentrations up to 320 mM (approximately 45 g L-1), which represents a great improvement in the aspect of the substrate concentration for the biocatalytic preparation of chiral sulfoxides.
