Pentanuclear anions

Addition of pyridine to Rh4(CO)i2 under a CO atmosphere affords the pentanuclear anionic rhodium salt cA-[Rh(CO)2(py)2][Rh5(CO)15] initially ... 

A novel class of chalcogen(II) halogen compounds was established recently by the preparation of the first simple binary mononuclear and oligomeric haloanions of divalent selenium and tellurium. The chemistry of these compounds is especially variable for selenium, and a number of highly interesting mono-, di-, tri, tetra- and pentanuclear anionic species with composition X Ym have been synthesized and characterized by structure analyses and spectroscopic studies up... 

Pyrolysis of [Os3(CO)nPy] in vacuo (523 K, 24 h) produces [OsioC(CO)24] , the largest osmium cluster known to date, in which the osmium atoms form a cubic-close-packed array. More delicate methods have led to the synthesis of the anion [Rh5(CO)io(iM2-CO)5] from the reaction between [Rh4(CO)i2] and [Rh(CO)4] in the THF under a CO atmosphere. This pentanuclear anion... 

We describe herein its conversion into the tetranuclear cluster anion [Co3Ru(CO)12] itself leading to the pentanuclear species Co3RuCu(CH3CN)(CO)12 in good yield. 

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