Octanuclear Rh-containing clusters

This nuclearity is still rather uncommon for Rh-containing clusters. Rh8C(CO)i9 has been obtained by oxidation of [Rh6C(CO)i5] and structurally characterized by X-ray analysis (see Fig. 14) no NMR data are presently available. 

The mono-capped octahedral cluster [Re7C(CO)2i] has been likened to Cp it adds to a variety of 12-electron [ML ]+ fragments, including [Rh(C0)2-xLx]+ (x = 0, 1, L = P-donor x = 2, L = COD) to produce a tra i-bicapped octahedral 

ReyRh-clusters.f Comparative NMR studies suggest [Re7C(CO)2i] is a weaker electron donor than Cp and reaction of [Re7C(CO)2i Rh(CO)2 ] with P-donors occurs exclusively on Rh. 

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