Direct Asymmetric Bromotrifluoromethoxylation of Alkenes with Trifluoromethyl Arylsulfonate as a New Trifluoromethoxylation Reagent
Pingping Tang reports the use of trifluoromethyl arylsulfonate as a new trifluoromethoxylation reagent.
Compounds containing fluorinated groups are receiving increasing attention in pharmaceuticals, agrochemicals and materials science. In particular, the trifluoromethoxy group has a high value because of its great electron-withdrawing effect and high lipophilicity. However, despite this strong and widespread interest, there are limited methods for synthesizing trifluoromethoxylated compounds which is mainly due to the low stability of trifluoromethoxide anions or transition-metal–trifluoromethoxide complexes. Therefore, new and efficient trifluoromethoxylating reagents are in great demand. To date, only a very limited number have been reported, with various limitations such as toxicity or difficulties in handling, as well as low reactivity.
Recently, the research group of Professor Pingping Tang at Nankai University (P. R. of China) discovered a new trifluoromethoxylation reagent, trifluoromethyl arylsulfonate (TFMS), and developed the first asymmetric silver-catalyzed intermolecular bromotrifluoromethoxylation of alkenes.