Substitution reactions on a hypercoordinated main-group element encapsulated in a pentacapped trigonal prismatic copper cage.

Compound 1, [Cu11(μ9-Br)(μ3-Br)3{S2P(O(i)Pr)2}6](+), containing the first μ9-bromide at the center of a pentacapped trigonal-prismatic copper skeleton, was isolated from the reaction of [Cu(CH3CN)4](PF6), NH4[S2P(O(i)Pr)2], and Bu4NBr in 11:6:4 ratios in methanol. Treatment of 1 with Bu4NI resulted in a complete replacement of four bromides to yield a corresponding iodo analogue {Cu11(I)(I)3[S2P(O(i)Pr)2]6}(+), 2. The central bromide and iodide in 1 and 2 can be replaced by a sulfide generated in situ from Na2S2O3 to produce [Cu11(μ9-S)(μ3-X)3{S2P(O(i)Pr)2}6] (X = Br, 3; I, 4).