Thionyl imide anion, NSO

A variety of complexes of the thionyl imide anion [NSO] with both early and late transition-metal complexes have been prepared and structurally characterized. Since both ionic and covalent derivatives of this anion are readily prepared, e.g., K[NSO], McsMNSO (M = Si, Sn) or Hg(NSO)2, metathetical reactions of these reagents with transition-metal halide complexes represent the most general synthetic method for the preparation of these complexes (Eq. 7.10 and 7.11). ... 

Salts of the [NSO] anion can be used for the synthesis of both transition-metal and main group element thionyl imides by metathetical reactions, e.g., Cp2Ti(NSO)2 and Ph3, .As(NSO)x (x = 1,2), respectively (Section 7.6). 

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