The first 3-dimensional assemblies of organotin-functionalized polyanions

Abstract

Reaction of the (CH₃)₂Sn²⁺ electrophile toward trilacunary [A-α-XW₉O₃₄]ⁿ⁻ Keggin polytungstates (X = P^V, As^V, Si^IV) with guanidinium as templating-cation resulted in the isostructural compounds Na[C(NH₂)₃]₂[{(CH₃)₂Sn(H₂O)}₃(A-α-PW₉O₃₄)]·9H₂O (1), Na[C(NH₂)₃]₂[{(CH₃)₂Sn(H₂O)}₃(A-α-AsW₉O₃₄)]·8H₂O (2) and Na₂[C(NH₂)₃]₂[{(CH₃)₂Sn(H₂O)}₃(A-α-SiW₉O₃₄)]·10H₂O (3). Compounds 1–3 constitute the first 3-dimensional assemblies of organotin-functionalized polyanions, as well as the first example of a dimethyltin-containing tungstosilicate in the case of 3, and they show a similar chiral architecture based on tetrahedrally-arranged {(CH₃)₂Sn}₃(A-α-XW₉O₃₄) monomeric building-blocks connected via intermolecular Sn–OW bridges regardless of the size and/or charge of the heteroatom.