Synthesis of Transition Metal Nitrosyl Compounds

A variety of methods are available to the inorganic chemist for the synthesis of nitrosyl complexes. Some examples of the most widely used routes are discussed next more exhaustive accounts have been given by Connelly (2), Caulton (4), and Gladfelter (11). 

If we pass gaseous nitric oxide through a solution of a coordinatively unsaturated transition metal complex, simple addition may occur. Since nitric oxide contains an unpaired electron, this method is most commonly applied to paramagnetic starting materials. Some examples of this reaction (16, 17) are 

Alternatively, the addition of the nitrosonium ion, generally as the tetrafluoroborate or hexafluorophosphate salt, provides a convenient synthetic route to nitrosyl complexes. Examples of such reactions include (18, 19) 

Reduction of the nitrosyl group occurs in certain cases, providing an effective method for the synthesis of nitrido clusters. For example (19)  

Substitution of Two-, Three-, Four-, and Five-Electron Ligands 

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