2,2,2-Trifluoroethyl aryl selenides: ArSeCH2CF3 (Ar=C6H5,p-CH3C6H4) and their derivatives ArSe(O)CH2CF3 and ArSe(X)2CH2CF3 (X=Cl, Br, OOCCF3)

Abstract The title selenides were prepared in good yield by reacting the appropriate aryl selenolate anions with 2,2,2-trifluoroethyl tosylate in refluxing tetrahydrofuran. These unsymmetrical bivalent selenides can be oxidised to the corresponding compounds of tetravalent selenium, ArSe(X) 2 CH 2 CF 3 (X = Cl and Br) with elemental chlorine and bromine. The latter, upon basic hydrolysis, gave the selenoxides, ArSe(O)CHCF 3 . Selenoxides have also been formed by direct reaction of the selenides with hydrogen peroxide. Upon reaction with trifluoroacetic anhydride, these gave trifluoroacetate derivatives, ArSe(OOCCF 3 ) 2 CH 2 CF 3 , in quantitative yield. The compounds have been characterized via elemental analysis, infrared spectra, 1 H and 19 F NMR spectra, and mass spectra.