Carbonyl clusters open triangular

X-ray diffraction of the PPN salt reveals a tetrahedral cluster of iron atoms (Fig. 5.14(c)). One triangular face is capped by a triply bridging CO group around each of the sides of this same face there is an edge-bridging carbonyl. On protonation the tetrahedral cluster opens out to a butterfly framework (cf. p. 350) the protonated CO ligand is now a-bonded to the fourth iron atom. Further reduction under acid conditions affords methane it has been suggested that this... 

The monosubstituted selenido-carbonyl open-triangular mdo-c ustcv Ru3(/i3-Se)2(GO)s(L) (L = tripyrrolidino-phosphine, tpnp), formed from the reaction of Ru3(GO)i2 with tpnpSe, reacts with tris(/ -methoxyphenyl)phosphine and l,2-bis(diphenylphosphinomethyl)benzene (dpmb), giving respectively, the di- and trisubstituted Ru3(/i3-Se)2(GO)6(tpnp)(dpmb) and Ru3(//3-Se)2(G0)7(tpnp) P(G6H40Me)3 clusters. 

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