Trifluoromethanesulfenamides: new reagents for direct S-CF3 bond formation
Because of its high lipophilicity, the CF3S group presents some potentialities in various applications and more specifically in life sciences. However, despite this growing interest the synthesis of trifluoromethylthiolated compounds was, until recently, few developed. Trifluoromethanesulfenamides are new compounds very easy to prepare, even in large scale, recently described. These trifluoromethanesulfenamides constitute a family of stable, versatile, very efficient and easy to handle reagents. These reagents can be engaged in a large panel of various reactions as electrophilic as well as nucleophilic species.
Because of the specific properties of the fluorine atom, fluorinated compounds are more and more used in a large panel of applications, from materials science to life sciences (1-5). With the diversity of fluorinated groups, properties of molecules can be modulated to obtain specific characteristics for the targeted products. In particular, association of the trifluoromethyl group with a heteroatom brings, in general, very specific and interesting properties. These last years, the trifluoromethylsulfanyl group (CF3S) has known a renewed interest, in particular due to its high lipophilicity (Hansch parameter πR = 1.44) (6-8). Such an induced lipophilicity is, particularly, of great interest in drug design by favoring transmembrane permeation of CF3S-substituted molecules, which, consequently, improves their bioavailability (9). Today, numerous methods to obtain CF3S-substituted compounds have been described in literature (10, 11). These recent strategies can be divided following three approaches. The indirect methods based on the trifluoromethylation of sulfur compounds necessitate the preliminary preparation of sulfur ...