Open hydrogen, insertion

Addition of a rhodium carbenoid to an alkyne leads to a cyclopropene derivative. In an intramolecular context, the fused cyclopropene moiety is unstable and undergoes ring opening to generate a rhodium vinyl carbenoid entity, which can then undergo cyclopropanation or cyclopropena-tion, carbon hydrogen insertion, and ylide generation. This is illustrated... 

Vinylcyclopropanes can react with pentacarbonyliron to give two different types of addition products i) (diene)tricarbonyliron 7r-complexes as the result of ring opening, hydrogen shift, and complexation ii) cyclohexenones by photoinduced carbonyl insertions across the vinyl-cyclopropane system. 

Figure 2.6. The tetrahedral structures of ice (a), (fc) are planes through sheets of selected oxygen nuclei (open circles), hydrogen nuclei (shotm in the insert as solid circles) are not shown in the main drawing. The insert illustrates the overlap of oxygen line pairs and the hydrogen nuclei, thus forming the hydrogen bonds (dotted lines)...

T. Jarrosson, G.-W. Wang, M. D. Bartberger, G. Schick, M. Saunders, R. J. Cross, K. N. Hock, Y. Rubin, Insertion of Helium and Molecular Hydrogen Inside an Open Fullerene , manuscript in preparation. 

However, separation of the carborane cage from The phos-phazene ring or chain by a methylene spacer group allows metals to be Inserted into the open face of the carborane. These syntheses were accomplished by the reaction routes shown in Schemes 3 and A. High polymeric analogues of these transformations have also been accomplished following polymerization of XXX. The rhodium-bound cyclophosphazenes and polyphosphazenes are catalysts for the hydrogenation of 1-hexene. In this, they show a similar behavior to metallocarboranes linked to polystyrene... 

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