Isomerization by partial reductive elimination

Recognition of j -H2 complexes as likely intermediates in oxidative addition reactions to d ions or reductive eliminations from d metal ions prompts examination of another possible complication to the intimate mechanism of d square-planar metal-ion reactions. Although none have been isolated, it seems reasonable to expect such species as intermediates in reductive eliminations from d complexes also, and a number of site fluxionality cases have been explained this way. 

Clark and co-workers reported vt NMR measurements on the compounds 32 (207). The compounds are fluxional, and above room 

These observations offer possible explanations for some site exchanges or isomerizations that have either been explained in other ways or lack a convincing explanation at all. The intramolecular phosphine scrambling in diamagnetic [NiH(PR3)s]+, rationalized in terms 

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