Preparation and structure of the unique silicon(iv) cation [SiF3(Me3tacn)]+

The trifluorosilicon(iv) cation [SiF(3)(Me(3)tacn)](+), isolated as salts with [SiF(5)](-), [B{3,5-(CF(3))(2)C(6)H(3)}(4)](-) or Cl(-), is obtained by reaction of SiF(4) with Me(3)tacn under anhydrous conditions, and compared with the tetrafluoro complexes [SiF(4)(tmeda)] and [SiF(4){kappa(2)-Me(2)N(CH(2))(2)NMe(CH(2))(2)NMe(2)(CH(2)Cl)}][SiF(5)] obtained with the acyclic di- and tri-amines.