Insertion of γ-SO3 into Perfluoroalkyl- and Polyfluoroalkoxysilanes

Abstract

The reactions of γ-SO3 with the silanes RfSi(CH3)3 [Rf = CF3 (1), C6F5 (2), CF2=CF (3), CF2=CFCH2CH2 (8), and RfSi(n-C3H7)3 [Rf = CF2=CF (7), CF2=CFCH2CH2 (9)] are reported. Several of the expected silyl sulfonates RfSO2OSi(CH3)3 [(Rf = CF3 (4), C6F5 (5), CF2=CF (6)] are isolated. The polyfluoroalkenyltin compound CF2=CFCH2CH2Sn(CH3)3 (10) is prepared, and also reacted with γ-SO3; however, the tin sulfonate does not form. With fluorinated siloxanes RfOSi(CH3)3 [Rf = (CF3)2CH (11), (CF3)2C(CH3) (12), (CF3)2C(C6H5) (13), CF3CH2 (14), (CF3)3C (15), (CH2CF2)2 (16)] reactions with γ-SO3 give the respective silyl sulfate esters RfOSO2-OSi(CH3)3 in yields up to 85%. The acids CF2=CFSO3H (25) and (HO3SOCH2CF2)2 (26) are easily obtained by the hydrolysis of 6 and 22, respectively. The compounds prepared in this study are characterized by 1H, 19F and 29Si NMR, IR and mass spectrometry. © 1994, American Chemical Society. All rights reserved.