Neutral Homoleptic Zinc, Cadmium and Mercury Amides

2 Neutral Homoleptic Zinc, Cadmium and Mercury Amides 

In contrast, the number of known structures of homoleptic, monomeric two-coordinate amides of cadmium is currently limited to just one example. The structure of the compound [Cd N(SiMe3)2 2] has been determined by electron diffraction and the data showed that it has a linear NCdN skeleton with a Cd—N bond length of 2.03(2) A. It is clear, however, that several other homoleptic cadmium amides (known and others as yet not synthesized) can be predicted to have monomeric structures in the solid state. For example Cd NMR studies of amides such as [Cd N(SiMe3)2 2] or [Cd N(SiMe2Ph)2 2] indicate that they are 

The key to the stabilization of two-coordinate monomeric stractures is obviously ligand size however, the metal also plays a role because in the case of zinc and cadmium the tendency to associate is more marked than it is for mercury. An example is provided by the monomeric strucmre observed for [Hg N(SiMe3)Ph 2], 

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