A deeper insight into direct trifluoromethoxylation with trifluoromethyl triflate

Commercially available fluorides (silver fluoride and n-tetrabutylammonium triphenyldifluorosilicate), combined with TFMT, allow a simple generation, in situ, of silver and n-tetrabutylammonium trifluoromethoxides which were able to react with electrophilic substrates. Silver trifluoromethoxide, which is usually more efficient than n-tetrabutylammonium trifluoromethoxide, converts, under mild conditions, primary aliphatic bromides and iodides, as well as primary and secondary benzylic or allylic bromides to the corresponding trifluoromethoxylated compounds. Several trifluoromethyl ethers, which could be valuable building-blocks, were prepared in such a way. (C) 2009 Elsevier B.V. All rights reserved.