Formation of a “less stable” polyanion directed and protected by electrophilic internal surface functionalities of a capsule in growth: [{Mo6O19}2−⊂{Movi72Feiii30O252(ac)20(H2O)92}]4−

Abstract

The spherical capsule skeleton of the host–guest system [{Mo₆O₁₉}²⁻⊂{Mo^VI ₇₂Fe^III ₃₀O₂₅₂(CH₃COO)₂₀(H₂O)₉₂}]⁴⁻1a—built up by 12 {(Mo^VI)Mo^VI ₅} type pentagonal units linked by 30 Fe^III centers which span the unique icosahedral Archimedean solid, the icosidodecahedron—can now be constructed deliberately and with a simpler composition than before from an acidified aqueous molybdate solution containing the mentioned (virtual) pentagonal units; the encapsulated hexamolybdate—normally not formed in water—is built up in an unprecedented way concomitant with capsule growth, while being directed by the corresponding internal electrophilic surface functionalities.