Fluorinated organic compounds are becoming increasingly important in pharmaceuticals, agrochemicals and materials science. The introduction of trifluoromethoxy groups into new drugs and agrochemicals has attracted much attention due to their strongly electron-withdrawing nature and high lipophilicity. However, synthesis of trifluoromethoxylated organic molecules is challenging because of the decomposition of trifluoromethoxide anion and β-fluoride elimination from transitionmetal–trifluoromethoxide complexes.
a, Compared to traditional trifluoromethoxylation reagents, TFMS is easily prepared and thermally stable with good reactivity. b, In the presence of silver salts and fluoride, TFMS could be used as a new trifluoromethoxylation reagent to generate AgOCF3 in situ, which was used for bromotrifluoromethoxylation of alkenes. c, The first example of an asymmetric silver-catalysed intermolecular bromotrifluoromethoxylation of alkenes with TFMS as a new trifluoromethoxylation reagent was described. This reaction is operationally simple, scalable and proceeds under mild reaction conditions with excellent functional group tolerance.(from Nature Chemistry)
Rencently, professor Tang Pingping, from Nankai University, published an important article on Nature Chemistry, representing an example of an asymmetric silver-catalysed intermolecular bromotrifluoromethoxylation of alkenes with trifluoromethyl arylsulfonate (TFMS) as a new trifluoromethoxylation reagent. Compared with other trifluoromethoxylation reagents, TFMS is easily prepared and thermally stable with good reactivity.
In addition, experiments of the bromotrifluoromethoxylation of double bonds in natural products and natural product derivatives have demonstrated the good functional group compatibility of the reaction. It tolerates a wide range of functional groups and is amenable to gram-scale synthesis. With its operational simplicity and mild conditions, this method will play a part in various applications of pharmaceutical and agrochemical research, as well as the development of the synthesis of trifluoromethoxylated compounds.
Link: http://www.nature.com/nchem/journal/vaop/ncurrent/full/nchem.2711.html
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