Isolation of a Labile Homoleptic Diazenium Cation

Following our interest in nitrogen chemistry, we now describe the synthesis, structure, and bonding of labile disilylated diazene, its GaCl3 adduct, and the intriguing trisilylated diazenium ion [(Me3Si)(2)NN-SiMe3](+), a dark blue and highly labile (T-decomp>-30 degrees C) homoleptic cation of the type [R3N2](+). Although direct silylation of Me3Si-NN-SiMe3 failed, the [(Me3Si)(2)NN-SiMe3](+) ion was generated in a straightforward two-electron oxidation reaction from mercury(II) dihydrazide and Ag[GaCl4]. Moreover, previous structure data of Me3Si-NN-SiMe3 were revised on the basis of new data.