Perfluoroalkylated Arsoranide Salts: Syntheses and Structural Insights

Herein we report the synthesis and structural characterization of perfluoroalkylated arsoranide salts. Complementary quantum chemical calculations provide initial insights into the stability of the corresponding anions. Treatment of As(CF 3 ) 2 I and As(C 2 F 5 ) 2 X (X = Br, Cl) with the tetraphenylphosphonium halide salts [PPh 4 ]X (X = I, Br, Cl) affords the diorganyl arsoranide salts [PPh 4 ][As(CF 3 ) 2 I 2 ] and [PPh 4 ][As(C 2 F 5 )X 2 ] (X = Br, Cl) in high yields. For the introduction of fluoride ligands, AgF and CsF were employed as fluoride sources. While CsF enables the selective formation of the metal arsoranide salt Cs[As(C 2 F 5 ) 2 F 2 ], the reaction with AgF results only in a halide exchange. However, in the presence of [PPh 4 ]Cl, the corresponding arsoranide salts [PPh 4 ][AsR 2 F 2 ] (R = CF 3, C 2 F 5 ) are obtained. Treatment of As(CF 3 )I 2 and As(C 2 F 5 )X 2 (X = Br, Cl) with [PPh 4 ]X furnishes monoorganyl arsoranide salts [PPh 4 ][As(CF 3 )I 3 ] and [PPh 4 ][As(C 2 F 5 )X 3 ] (X = Br, Cl).