New Electrophilic Trifluoromethylating Agents

Abstract

Synthetic routes to S-(trifluoromethyl)phenyl-4-fluorophenylsulfonium triflate (8), S-(trifluoromethyl)phenyl-2,4-difluorophenylsulfonium triflate (9), S-(trifluoromethyl)phenyl-3-nitrophenylsulfonium triflate (10), and S-(trifluoromethyl)-4-fluorophenyl-3-nitrophenylsulfonium triflate (11) are described. They are stable molecules and conveniently prepared by treating phenyl trifluoromethyl sulfoxide with benzene and its derivatives. These novel electrophilic trifluoromethylating agents react under mild conditions with a variety of aromatic rings (p-hydroquinone, pyrrole, and aniline) to give trifluoromethylated compounds (2-trifluoromethyl-p-hydroquinone, 2-trifluoromethylpyrrole, 2-trifluoromethylaniline, and 4-trifluoromethylaniline) in moderate to high yields. The electrophilic trifluoromethylating potential can be altered by placing electron-withdrawing substituents on the benzene rings.

Gas‐phase structure and new vibrational study of methyl trifluoroacetate (CF3C(O)OCH3)

“…Experimental radial distribution curve and theoretical-minusexperimental difference curve for the refinement of CF 3 C(O)OCH 3 . Before Fourier inversion, the data were multiplied by s · exp(−0.00002s 2 …”

“…[1] The powerful electron-withdrawing ability and the relatively small size of the trifluoromethyl group can bring remarkable changes in the physical, chemical and biological properties of molecules, making them suitable for diverse applications in the areas of materials science and the pharmaceutical and agrochemical industries. [2,3] It is therefore desirable to investigate and understand the fundamental properties of such fluorinated organic compounds. In that way, the studies made on trifluoroethyl trifluoroacetate [4] in this laboratory have been extended to include methyl trifluoroacetate, in order to gain structural information relating to possible conformational isomerism and vibrational information relating to the force constants.…”

Benchmark and Solvent‐Free Preparation of Sulfonium Salt Based Electrophilic Trifluoromethylating Reagents

“…The first series of sulfur-based trifluoromethylating compounds 1 were described earlier by Yagupolskii et al in 1984. [9] Alternative routes for the preparation of these reagents were proposed by Shreeve and coworkers [10] and very recently again by Yagupolskii. [11] During this time, great improvements have been made by Umemoto et al with the design of numerous dibenzothiophenium salts 4.…”

Sulfoximines as a Versatile Scaffold for Electrophilic Fluoroalkylating Reagents

“…The first one, inspired by the pioneering work of Yagupolskii, [2] is based on the sulfonium skeletons. Many teams have contributed to the growth of this family which now covers not only the electrophilic trifluoromethylation reaction (Shreeve, [3] Umemoto, [4] Shibata, [5] and ourselves [6] ), but also the mono-and difluoroalkylation (Prakash and Olah) [7] and pentafluoroethylation reactions. [8] The second series of molecules, hypervalent iodine(III)-CF 3 reagents, was proposed by Togni.…”