An interesting metallacarborane cage closure and dismantling reaction including the facile halogenation of a cluster carbon atom: Structure of [1,2-(η5-C5Me5)2-μ-1,2-H-closo-1,2,3-Rh2CB4H4-3-I]

With an approximately molar equivalent of iodine and excess of triethylamine [2,5-(η5-C5Me5)2-10-Me-μ-2,5-H-nido-2,5,1-Rh2CB6H8] expels two boron cluster vertices and undergoes a cage-closure reaction, resulting in the formation of a seven-vertex closo species of constitution [1,2-(η5-C5Me5)2-μ-1,2-H-closo-1,2,3-Rh2CB4H4-3-I] (see figure), isolatable in good yield (79%).