Synthesis of Poly- And the First Perfluoroalkyl-N(SO2F)2 Derivatives: Improved Methods for the Preparation of XN(SO2F)2 (X = H, Cl) and Single-Crystal Diffraction Studies of HN(SO2Cl)2, HN(SO2F)2, and CF3CH2N(SO2F)2

Abstract

The preparation of HN(SO2F)2 was achieved conveniently by fluorination of HN(SO2C1)2 with SbF3. Reactions of Hg[N(SO2F)2]2 with fluoroalkyl iodides RI (R = i-C3F7CH2CH2 and CF3CH2) gave i-C3F7CH2CH2N(SO2F) 2 (1) and CF3CH2N(SO2F)2 (2). The chlorination of Hg[N(SO2F)2]2 provided a high-yield method of synthesizing the well-known ClN(SO2F)2. N-alkylation of ClN(SO2F)2 with fluorinated ethenes CF2=CHal2 (CHal2 = CF2, CFCl, and CCl2) resulted in the formation of CF2ClCF2N(SO2F)2 (3), CF2ClCFClN(SO2F)2 (4a, major), CFCl2-CF2N(SO2F)2 (4b, minor), and CCl3CF2N(SO2F)2 (5). The synthesis of the first perfluoroalkyl-N(SO2F)2 derivatives CF3N(SO2F)2 (6), C2F5N(SO2F)2 (7), n-C3F7N(SO2F)2 (8), and n-C4F9N(SO2F)2 (9) was accomplished with moderate-to-good yields by reacting ClN(SO2F)2 with iodoperfluoroalkanes RFI (RF = CF3, C2F5, n-C3F7, and n-C4F9). Similarly, ClN(SO2F)2 reacted with CF3CH2I to give 2. Photolysis of ClN(SO2F)2 with iodoperfluoroalkanes RFI (RF = n-C3F7, and n-C4F9) gave 8 and 9 in low yields. HN(SO2F)2 belongs to a monoclinic crystal system P21 (No. 4): a = 5.1619(5) Å, b = 7.8153(8) Å, c = 6.8028(7) Å, β = 100.411(2)°, V= 269.92(5) Å3, Z= 2. HN(SO2Cl)2 is monoclinic P21/c (No. 14): a = 7.7331(3) Å, b = 10.0542(2) Å, c = 9.3197(3) Å, β = 109.495(1)°, V = 683.07(4) Å3, Z= 4. CF3CH2N(SO2F)2 is orthorhombic P212121 (No. 19): a= 11.1245(1) Å, b = 28.8003(4) Å, c = 7.7120 Å, V = 2470.90(4) Å3, Z = 12.