Nucleophilic difluoromethylation and trifluoromethylation using tetrakis(dimethylamino)ethylene (TDAE) reagent

In an effort to find new methodologies to introduce difluoromethylene and trifluoromethyl moieties into organic molecules of synthetic and biological interest, tetrakis(dimethylamino)ethylene (TDAE) was found to be an effective reductant of a series of good electron-acceptors such as bromodifluoromethyl heterocycles, chlorodifluoromethylated ketones as well as perfluoroalkyl iodides; the corresponding anions thus generated under very mild conditions, were successfully engaged in a number of intra-and intermolecular coupling reactions with a series of electrophiles (aldehydes, ketones, alpha-keto esters, N-tosyl aldimines, acyl chlorides, diol sulphates, disulfides, and diselenides). The corresponding adducts were usually obtained in moderate to good yields and the present method was found to be as good or even better as other most popular approaches. This paper gives an overview of our research efforts in this area as well as results from other groups. (C) 2008 Elsevier B.V. All rights reserved.